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Structure Your Database  |  Firebase

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class="devsite-nav-title"><span class="devsite-nav-text" tooltip>iOS</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/android/setup" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Android</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/web/setup" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Web</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Add Firebase to a game</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/games/setup" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Overview</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cpp/setup" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>C++</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/unity/setup" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Unity</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/admin/setup" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Add Firebase to a server</span></a></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Use Firebase with a framework</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/flutter/setup" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Flutter</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-beta"><a href="/web/20201022183222/https://firebase.google.com/docs/projects/api/workflow_set-up-and-manage-project" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Set up projects programmatically</span><span class="devsite-nav-icon material-icons" data-icon="beta" data-title="Beta" aria-hidden="true"></span></a></li></ul></devsite-expandable-nav></li> <li class="devsite-nav-item devsite-nav-expandable devsite-nav-accordion"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Manage your Firebase projects</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/projects/learn-more" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Understand Firebase projects</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/projects/locations" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Select locations for your project</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/projects/multiprojects" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Configure multiple projects</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/projects/pwa" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Use Firebase in PWAs</span></a></li><li class="devsite-nav-item devsite-nav-beta"><a href="/web/20201022183222/https://firebase.google.com/docs/projects/bigquery-export" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Export project data to BigQuery</span><span class="devsite-nav-icon material-icons" data-icon="beta" data-title="Beta" aria-hidden="true"></span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/projects/manage-installations" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Manage Firebase installations</span></a></li><li class="devsite-nav-item devsite-nav-beta"><a href="/web/20201022183222/https://firebase.google.com/docs/projects/import-segments" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Import segments</span><span class="devsite-nav-icon material-icons" data-icon="beta" data-title="Beta" aria-hidden="true"></span></a></li><li class="devsite-nav-item devsite-nav-heading"><div class="devsite-nav-title devsite-nav-title-no-path"><span class="devsite-nav-text" tooltip>Manage projects programmatically</span></div></li><li class="devsite-nav-item devsite-nav-beta"><a href="/web/20201022183222/https://firebase.google.com/docs/projects/api/workflow_set-up-and-manage-project" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Use the REST API</span><span class="devsite-nav-icon material-icons" data-icon="beta" data-title="Beta" aria-hidden="true"></span></a></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Use the Admin SDK</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/reference/admin/node/admin.projectManagement" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Node.js</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/reference/admin/java/reference/com/google/firebase/projectmanagement/package-summary" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Java</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/reference/admin/python/firebase_admin.project_management" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Python</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/projects/provisioning/configure-oauth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Configure OAuth identity providers for Firebase Auth</span></a></li><li class="devsite-nav-item devsite-nav-heading"><div class="devsite-nav-title devsite-nav-title-no-path"><span class="devsite-nav-text" tooltip>Manage project access (IAM)</span></div></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/projects/iam/overview" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Overview</span></a></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Roles</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/projects/iam/roles" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Overview</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/projects/iam/roles-primitive" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Owner, Editor, Viewer roles</span></a></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Firebase predefined roles</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/projects/iam/roles-predefined" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Overview</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/projects/iam/roles-predefined-all-products" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Firebase-level roles</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/projects/iam/roles-predefined-category" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Product-category roles</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/projects/iam/roles-predefined-product" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Product-level roles</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/projects/iam/roles-custom" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Custom roles</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/projects/iam/permissions" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Permissions</span></a></li></ul></devsite-expandable-nav></li> <li class="devsite-nav-item devsite-nav-expandable devsite-nav-accordion devsite-nav-beta"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Prototype and test with Emulator Suite</span><span class="devsite-nav-icon material-icons" data-icon="beta" data-title="Beta" aria-hidden="true"></span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/emulator-suite" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Introduction</span></a></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Connect your app and prototype</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/emulator-suite/connect_and_prototype" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get started</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/emulator-suite/connect_rtdb" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Connect to the Realtime Database emulator</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/emulator-suite/connect_firestore" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Connect to the Cloud Firestore emulator</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/emulator-suite/connect_functions" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Connect to the Cloud Functions emulator</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/emulator-suite/install_and_configure" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Install, configure and integrate</span></a></li></ul></devsite-expandable-nav></li> <li class="devsite-nav-item devsite-nav-expandable devsite-nav-accordion"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Analytics</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/analytics" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Introduction</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/analytics/get-started" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get Started</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/analytics/events" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Log Events</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/analytics/user-properties" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Set User Properties</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/analytics/debugview" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Debug Events</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/analytics/screenviews" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Track Screens</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/analytics/userid" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Set a User ID</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/analytics/measure-ecommerce" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Measure Ecommerce</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/analytics/webview" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Use in a WebView</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/analytics/extend-with-functions" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Extend with Cloud Functions</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/analytics/configure-data-collection" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Configure Data Collection and Usage</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/analytics/errors" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Error Codes</span></a></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>C++</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/analytics/cpp/start" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get Started</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/analytics/cpp/events" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Log Events</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/analytics/cpp/properties" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Set User Properties</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Unity</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/analytics/unity/start" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get Started</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/analytics/unity/events" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Log Events</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/analytics/unity/properties" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Set User Properties</span></a></li></ul></devsite-expandable-nav></li></ul></devsite-expandable-nav></li> <li class="devsite-nav-item devsite-nav-expandable devsite-nav-accordion devsite-nav-beta"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Extensions</span><span class="devsite-nav-icon material-icons" data-icon="beta" data-title="Beta" aria-hidden="true"></span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/extensions" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Introduction</span></a></li><li class="devsite-nav-item devsite-nav-heading"><div class="devsite-nav-title devsite-nav-title-no-path"><span class="devsite-nav-text" tooltip>Use an extension in your project</span></div></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/extensions/overview-use-extensions" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Overview</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/extensions/install-extensions" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Install an extension</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/extensions/manage-installed-extensions" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Manage installed extensions</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/extensions/permissions-granted-to-extension" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Permissions granted to an extension</span></a></li></ul></devsite-expandable-nav></li> <li class="devsite-nav-item devsite-nav-divider devsite-nav-heading"><div class="devsite-nav-title devsite-nav-title-no-path"><span class="devsite-nav-text" tooltip>Develop</span></div></li> <li class="devsite-nav-item devsite-nav-expandable devsite-nav-accordion"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Authentication</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Introduction</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/where-to-start" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Where do I start?</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/users" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Users in Firebase Projects</span></a></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>iOS</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/ios/firebaseui" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Sign in with a pre-built UI</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/ios/start" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get Started</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/ios/manage-users" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Manage Users</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/ios/password-auth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Password Authentication</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/ios/email-link-auth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Email Link Authentication</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/ios/google-signin" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Google Sign-In</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/ios/facebook-login" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Facebook Login</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/ios/apple" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Sign in with Apple</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/ios/twitter-login" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Twitter Login</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/ios/github-auth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>GitHub</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/ios/microsoft-oauth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Microsoft</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/ios/yahoo-oauth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Yahoo</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/ios/game-center" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Game Center Sign-in</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/ios/phone-auth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Phone Number</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/ios/custom-auth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Use a Custom Auth System</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/ios/anonymous-auth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Anonymous Authentication</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/ios/single-sign-on" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Enabling cross-app authentication with shared iOS Keychain</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/ios/account-linking" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Link Multiple Auth Providers</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/ios/passing-state-in-email-actions" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Passing State in Email Actions</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/ios/errors" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Handle Errors</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Android</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/android/firebaseui" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Sign in with a pre-built UI</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/android/start" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get Started with the Firebase SDK</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/android/manage-users" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Manage Users</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/android/password-auth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Password Authentication</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/android/email-link-auth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Email Link Authentication</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/android/google-signin" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Google Sign-In</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/android/facebook-login" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Facebook Login</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/android/apple" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Sign in with Apple</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/android/twitter-login" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Twitter</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/android/github-auth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>GitHub</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/android/microsoft-oauth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Microsoft</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/android/yahoo-oauth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Yahoo</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/android/play-games" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Play Games Sign-in</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/android/phone-auth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Phone Number</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/android/custom-auth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Use a Custom Auth System</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/android/anonymous-auth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Anonymous Authentication</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/android/account-linking" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Link Multiple Auth Providers</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/android/passing-state-in-email-actions" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Passing State in Email Actions</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Web</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/web/firebaseui" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Sign in with a pre-built UI</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/web/start" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get Started</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/web/manage-users" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Manage Users</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/web/password-auth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Password Authentication</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/web/email-link-auth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Email Link Authentication</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/web/google-signin" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Google Sign-In</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/web/facebook-login" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Facebook Login</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/web/apple" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Sign in with Apple</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/web/twitter-login" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Twitter</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/web/github-auth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>GitHub</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/web/microsoft-oauth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Microsoft</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/web/yahoo-oauth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Yahoo</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/web/phone-auth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Phone Number</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/web/custom-auth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Use a Custom Auth System</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/web/anonymous-auth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Anonymous Authentication</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/web/account-linking" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Link Multiple Auth Providers</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/web/cordova" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>OAuth Sign-In for Cordova</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/web/auth-state-persistence" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Auth State Persistence</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/web/passing-state-in-email-actions" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Passing State in Email Actions</span></a></li><li class="devsite-nav-item devsite-nav-beta"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/web/service-worker-sessions" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Service Worker Sessions</span><span class="devsite-nav-icon material-icons" data-icon="beta" data-title="Beta" aria-hidden="true"></span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>C++</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/cpp/start" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get Started</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/cpp/manage-users" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Manage Users</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/cpp/password-auth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Password Authentication</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/cpp/google-signin" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Google Sign-in</span></a></li><li class="devsite-nav-item devsite-nav-beta"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/cpp/play-games" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Play Games Sign-in</span><span class="devsite-nav-icon material-icons" data-icon="beta" data-title="Beta" aria-hidden="true"></span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/cpp/github-auth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>GitHub</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/cpp/facebook-login" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Facebook Login</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/cpp/apple" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Sign in with Apple</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/cpp/twitter-login" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Twitter Login</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/cpp/microsoft-oauth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Microsoft</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/cpp/yahoo-oauth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Yahoo</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/cpp/phone-auth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Phone Number</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/cpp/custom-auth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Use a Custom Auth System</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/cpp/anonymous-auth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Anonymous Authentication</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/cpp/account-linking" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Link Multiple Auth Providers</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Unity</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/unity/start" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get Started</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/unity/manage-users" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Manage Users</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/unity/password-auth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Password Authentication</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/unity/google-signin" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Google Sign-in</span></a></li><li class="devsite-nav-item devsite-nav-beta"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/unity/play-games" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Play Games Sign-in</span><span class="devsite-nav-icon material-icons" data-icon="beta" data-title="Beta" aria-hidden="true"></span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/unity/github-auth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>GitHub Authentication</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/unity/facebook-login" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Facebook Login</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/unity/apple" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Sign in with Apple</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/unity/twitter-login" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Twitter Login</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/unity/microsoft-oauth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Microsoft</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/unity/yahoo-oauth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Yahoo</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/unity/phone-auth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Phone Number</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/unity/custom-auth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Use a Custom Auth System</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/unity/anonymous-auth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Anonymous Authentication</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/unity/account-linking" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Link Multiple Auth Providers</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Admin</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/admin" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Introduction</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/admin/manage-users" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Manage Users</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/admin/import-users" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Import Users</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/admin/create-custom-tokens" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Create Custom Tokens</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/admin/verify-id-tokens" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Verify ID Tokens</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/admin/manage-sessions" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Manage User Sessions</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/admin/manage-cookies" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Manage Session Cookies</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/admin/custom-claims" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Control Access with Custom Claims</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/admin/email-action-links" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Generating Email Action Links</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/admin/errors" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Errors</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/admin/migrate-admin" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Migration Guide</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/custom-email-handler" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Customize the Email Action Handler</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/extend-with-functions" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Extend with Cloud Functions</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/case-studies" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Case Studies</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/auth/limits" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Usage Limits</span></a></li></ul></devsite-expandable-nav></li> <li class="devsite-nav-item devsite-nav-expandable devsite-nav-accordion"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Realtime Database</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Introduction</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/rtdb-vs-firestore" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Choose a Database</span></a></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>iOS</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/ios/start" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get Started</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/ios/structure-data" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Structure Data</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/ios/read-and-write" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Read and Write Data</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/ios/lists-of-data" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Work with Lists of Data</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/ios/offline-capabilities" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Enable Offline Capabilities</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Android</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/android/start" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get Started</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/android/structure-data" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Structure Data</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/android/read-and-write" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Read and Write Data</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/android/lists-of-data" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Work with Lists of Data</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/android/offline-capabilities" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Enable Offline Capabilities</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Web</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/web/start" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get Started</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/web/structure-data" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Structure Data</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/web/read-and-write" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Read and Write Data</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/web/lists-of-data" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Work with Lists of Data</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/web/offline-capabilities" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Enable Offline Capabilities</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Admin</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/admin/start" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get Started</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/admin/structure-data" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Structure Data</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/admin/save-data" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Save Data</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/admin/retrieve-data" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Retrieve Data</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>REST</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/rest/start" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get Started</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/rest/structure-data" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Structure Data</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/rest/save-data" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Save Data</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/rest/retrieve-data" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Retrieve Data</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/rest/auth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Authenticate REST Requests</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>C++</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/cpp/start" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get Started</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/cpp/structure-data" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Structure Data</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/cpp/save-data" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Save Data</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/cpp/retrieve-data" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Retrieve Data</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Unity</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/unity/start" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get Started</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/unity/structure-data" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Structure Data</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/unity/save-data" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Save Data</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/unity/retrieve-data" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Retrieve Data</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Security &amp; Rules</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/security" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Understand Rules</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/security/get-started" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get Started</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/security/core-syntax" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Structure Security Rules</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/security/rules-conditions" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Write Conditions for Security Rules</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/security/indexing-data" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Index Data</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/rest/app-management" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Manage Rules via REST</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Usage and Performance</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/usage/billing" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Understand Billing</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/usage/limits" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Realtime Database Limits</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/usage/monitor-usage" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Monitor Database Usage</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/usage/monitor-performance" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Monitor Database Performance</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/usage/sharding" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Scale with Multiple Databases</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/usage/profile" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Profile Your Database</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/usage/optimize" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Optimize Database Performance</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/backups" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Automated Backups</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/extend-with-functions" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Extend with Cloud Functions</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/database/video-series" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Video series: Firebase for SQL Developers</span></a></li></ul></devsite-expandable-nav></li> <li class="devsite-nav-item devsite-nav-expandable devsite-nav-accordion"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Cloud Firestore</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Introduction</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/quickstart" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get started</span></a></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Understand Cloud Firestore</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/rtdb-vs-firestore" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Compare Cloud Firestore and Realtime Database</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/data-model" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Data model</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/manage-data/data-types" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Data types</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/client/libraries" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>SDKs and client libraries</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/query-data/index-overview" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Index types</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/locations" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Database locations</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Add and manage data</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/manage-data/structure-data" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Structure data</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/manage-data/add-data" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Add data</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/manage-data/transactions" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Transactions and batched writes</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/transaction-data-contention" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Data contention in transaction</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/manage-data/delete-data" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Delete data</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/using-console" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Manage Cloud Firestore with the Firebase Console</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/manage-data/export-import" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Export and import data</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/manage-data/move-data" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Move data between projects</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Read data</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/query-data/get-data" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get data once</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/query-data/listen" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Listen for realtime updates</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/query-data/queries" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Perform simple and compound queries</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/query-data/order-limit-data" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Order and limit data</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/query-data/query-cursors" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Paginate data with query cursors</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/manage-data/enable-offline" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Access data offline</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/query-data/indexing" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Manage indexes</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Secure and validate data</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/security/overview" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Overview</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/security/get-started" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get started</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/security/rules-structure" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Structure Security Rules</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/security/rules-conditions" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Writing conditions for Security Rules</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/security/insecure-rules" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Fix insecure rules</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/security/test-rules-emulator" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Test your Security Rules</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/security/rules-query" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Securely query data</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Solutions</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/solutions" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Overview</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/solutions/aggregation" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Aggregation Queries</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/solutions/counters" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Distributed counters</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/solutions/search" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Full-text search</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/solutions/presence" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Build presence</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/solutions/role-based-access" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Secure data access for users and groups</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/solutions/delete-collections" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Delete data with a callable Cloud Function</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/solutions/schedule-export" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Schedule data exports</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/solutions/shard-timestamp" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Sharded timestamps</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/solutions/automate-database-create" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Automating database creation</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/solutions/index-map-field" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Reduce index costs with map fields</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Usage, limits, and pricing</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/quotas" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Usage and limits</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/monitor-usage" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Monitor usage</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/pricing" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Understand Cloud Firestore billing</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/billing-example" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Example Cloud Firestore costs</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/storage-size" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Understand storage size calculations</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/best-practices" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Best practices for Cloud Firestore</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Cloud Firestore integrations</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/use-rest-api" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Use the Cloud Firestore REST API</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/firestore-for-rtdb" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Use Cloud Firestore and Realtime Database</span></a></li><li class="devsite-nav-item devsite-nav-beta"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/extend-with-functions" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Extend with Cloud Functions</span><span class="devsite-nav-icon material-icons" data-icon="beta" data-title="Beta" aria-hidden="true"></span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/library-integrations" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Third-party library integrations</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>API reference</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/reference/android/com/google/firebase/firestore/package-summary" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Android</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/reference/swift/firebasefirestore/api/reference/Classes" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>iOS — Swift</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/reference/ios/firebasefirestore/api/reference/Classes" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>iOS — Objective-C</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/reference/js/firebase.firestore" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Web</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/reference/functions/providers_firestore_" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Cloud Functions</span></a></li><li class="devsite-nav-item"><a href="//web.archive.org/web/20201022183222/https://googleapis.dev/nodejs/firestore/latest/" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Node.js</span></a></li><li class="devsite-nav-item"><a href="//web.archive.org/web/20201022183222/https://googleapis.github.io/google-cloud-java/google-cloud-clients/apidocs/index.html?com/google/cloud/firestore/package-summary.html" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Java</span></a></li><li class="devsite-nav-item"><a href="//web.archive.org/web/20201022183222/https://googleapis.github.io/google-cloud-python/latest/firestore/client.html" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Python</span></a></li><li class="devsite-nav-item"><a href="//web.archive.org/web/20201022183222/https://godoc.org/cloud.google.com/go/firestore" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Go</span></a></li><li class="devsite-nav-item"><a href="//web.archive.org/web/20201022183222/https://googleapis.github.io/google-cloud-dotnet/docs/Google.Cloud.Firestore/" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>C#</span></a></li><li class="devsite-nav-item"><a href="//web.archive.org/web/20201022183222/https://googleapis.github.io/google-cloud-php/#/docs/cloud-firestore/latest/firestore/readme" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>PHP</span></a></li><li class="devsite-nav-item"><a href="//web.archive.org/web/20201022183222/https://googleapis.github.io/google-cloud-ruby/docs/google-cloud-firestore/latest/Google/Firestore/V1beta1" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Ruby</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/reference/rest" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>REST</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/reference/rpc" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>RPC</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Samples</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/client/samples-ios" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>iOS</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/client/samples-android" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Android</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/firestore/client/samples-web" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Web</span></a></li></ul></devsite-expandable-nav></li></ul></devsite-expandable-nav></li> <li class="devsite-nav-item devsite-nav-expandable devsite-nav-accordion"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Storage</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Introduction</span></a></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>iOS</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/ios/start" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get Started</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/ios/create-reference" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Create a Reference</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/ios/upload-files" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Upload Files</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/ios/download-files" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Download Files</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/ios/file-metadata" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Use File Metadata</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/ios/delete-files" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Delete Files</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/ios/list-files" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>List Files</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/ios/handle-errors" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Handle Errors</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Android</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/android/start" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get Started</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/android/create-reference" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Create a Reference</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/android/upload-files" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Upload Files</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/android/download-files" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Download Files</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/android/file-metadata" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Use File Metadata</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/android/delete-files" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Delete Files</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/android/list-files" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>List Files</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/android/handle-errors" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Handle Errors</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Web</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/web/start" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get Started</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/web/create-reference" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Create a Reference</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/web/upload-files" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Upload Files</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/web/download-files" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Download Files</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/web/file-metadata" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Use File Metadata</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/web/delete-files" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Delete Files</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/web/list-files" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>List Files</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/web/handle-errors" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Handle Errors</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Admin</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/admin/start" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get Started</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>C++</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/cpp/start" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get Started</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/cpp/create-reference" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Create a Reference</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/cpp/upload-files" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Upload Files</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/cpp/download-files" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Download Files</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/cpp/file-metadata" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Use File Metadata</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/cpp/delete-files" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Delete Files</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/cpp/handle-errors" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Handle Errors</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Unity</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/unity/start" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get Started</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/unity/create-reference" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Create a Reference</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/unity/upload-files" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Upload Files</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/unity/download-files" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Download Files</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/unity/file-metadata" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Use File Metadata</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/unity/delete-files" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Delete Files</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/unity/handle-errors" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Handle Errors</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Security &amp; Rules</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/security" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Understand Security</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/security/get-started" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get Started</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/security/core-syntax" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Structure Security Rules</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/security/rules-conditions" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Write Conditions for Security Rules</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/monitor-storage" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Monitor activity</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/extend-with-functions" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Extend with Cloud Functions</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/storage/gcp-integration" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Integrate with Google Cloud</span></a></li></ul></devsite-expandable-nav></li> <li class="devsite-nav-item devsite-nav-expandable devsite-nav-accordion"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Hosting</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/hosting" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Introduction</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/hosting/use-cases" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>What can you do with Firebase Hosting?</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/hosting/quickstart" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get started</span></a></li><li class="devsite-nav-item devsite-nav-new"><a href="/web/20201022183222/https://firebase.google.com/docs/hosting/test-preview-deploy" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Test, preview, then deploy</span><span class="devsite-nav-icon material-icons" data-icon="new" data-title="New!" aria-hidden="true"></span></a></li><li class="devsite-nav-item devsite-nav-new"><a href="/web/20201022183222/https://firebase.google.com/docs/hosting/github-integration" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Deploy via GitHub pull requests</span><span class="devsite-nav-icon material-icons" data-icon="new" data-title="New!" aria-hidden="true"></span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/hosting/multisites" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Share project resources across multiple sites</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/hosting/custom-domain" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Connect a custom domain</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/hosting/full-config" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Configure hosting behavior</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/hosting/i18n-rewrites" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Configure i18n rewrites</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/hosting/reserved-urls" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Add SDKs using reserved URLs</span></a></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Serve dynamic content and host microservices</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/hosting/serverless-overview" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Overview</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/hosting/functions" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Use Cloud Functions for Firebase</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/hosting/cloud-run" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Use Cloud Run</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/hosting/manage-cache" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Manage cache behavior</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/hosting/manage-hosting-resources" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Manage live &amp; preview channels, releases, and versions</span></a></li><li class="devsite-nav-item devsite-nav-new"><a href="/web/20201022183222/https://firebase.google.com/docs/hosting/web-request-logs-and-metrics" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Monitor web request data with Cloud Logging</span><span class="devsite-nav-icon material-icons" data-icon="new" data-title="New!" aria-hidden="true"></span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/hosting/usage-quotas-pricing" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Usage, quotas, and pricing</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/hosting/api-deploy" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Deploy using the REST API</span></a></li></ul></devsite-expandable-nav></li> <li class="devsite-nav-item devsite-nav-expandable devsite-nav-accordion"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Cloud Functions</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/functions" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Introduction</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/functions/use-cases" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>What can I do with Cloud Functions?</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/functions/get-started" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get started</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/functions/beta-v1-diff" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Upgrade to v1.0+ from beta</span></a></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Call functions directly</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/functions/callable" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Call functions from your app</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/functions/http-events" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Call functions via HTTP requests</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/functions/schedule-functions" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Run functions on a schedule</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Trigger background functions</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item devsite-nav-beta"><a href="/web/20201022183222/https://firebase.google.com/docs/functions/firestore-events" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Cloud Firestore triggers</span><span class="devsite-nav-icon material-icons" data-icon="beta" data-title="Beta" aria-hidden="true"></span></a></li><li class="devsite-nav-item devsite-nav-beta"><a href="/web/20201022183222/https://firebase.google.com/docs/functions/database-events" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Realtime Database triggers</span><span class="devsite-nav-icon material-icons" data-icon="beta" data-title="Beta" aria-hidden="true"></span></a></li><li class="devsite-nav-item devsite-nav-beta"><a href="/web/20201022183222/https://firebase.google.com/docs/functions/rc-events" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Remote Config triggers</span><span class="devsite-nav-icon material-icons" data-icon="beta" data-title="Beta" aria-hidden="true"></span></a></li><li class="devsite-nav-item devsite-nav-beta"><a href="/web/20201022183222/https://firebase.google.com/docs/functions/auth-events" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Authentication triggers</span><span class="devsite-nav-icon material-icons" data-icon="beta" data-title="Beta" aria-hidden="true"></span></a></li><li class="devsite-nav-item devsite-nav-beta"><a href="/web/20201022183222/https://firebase.google.com/docs/functions/analytics-events" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Analytics triggers</span><span class="devsite-nav-icon material-icons" data-icon="beta" data-title="Beta" aria-hidden="true"></span></a></li><li class="devsite-nav-item devsite-nav-deprecated"><a href="/web/20201022183222/https://firebase.google.com/docs/functions/crashlytics-events" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Crashlytics triggers</span><span class="devsite-nav-icon material-icons" data-icon="deprecated" data-title="Deprecated" aria-hidden="true"></span></a></li><li class="devsite-nav-item devsite-nav-beta"><a href="/web/20201022183222/https://firebase.google.com/docs/functions/gcp-storage-events" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Cloud Storage triggers</span><span class="devsite-nav-icon material-icons" data-icon="beta" data-title="Beta" aria-hidden="true"></span></a></li><li class="devsite-nav-item devsite-nav-beta"><a href="/web/20201022183222/https://firebase.google.com/docs/functions/pubsub-events" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Cloud Pub/Sub triggers</span><span class="devsite-nav-icon material-icons" data-icon="beta" data-title="Beta" aria-hidden="true"></span></a></li><li class="devsite-nav-item devsite-nav-beta"><a href="/web/20201022183222/https://firebase.google.com/docs/functions/test-lab-events" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Test Lab triggers</span><span class="devsite-nav-icon material-icons" data-icon="beta" data-title="Beta" aria-hidden="true"></span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Write functions</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/functions/manage-functions" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Manage deployment and runtime options</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/functions/typescript" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Write functions in TypeScript</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/functions/terminate-functions" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Sync, async, and promises</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/functions/retries" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Retry asynchronous functions</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/functions/config-env" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Environment configuration</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/functions/organize-functions" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Organize functions</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/functions/handle-dependencies" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Handling dependencies</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/functions/networking" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Optimizing networking</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/functions/tips" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Tips &amp; tricks</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Test functions</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/functions/local-emulator" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Run functions locally</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/functions/unit-testing" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Unit testing functions</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/functions/local-shell" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Test functions interactively</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Monitor functions</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/functions/writing-and-viewing-logs" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Write and view logs</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/functions/reporting-errors" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Report errors</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/functions/monitored-metrics" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>View monitored metrics</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>API Reference</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/reference/functions" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Firebase SDK for Cloud Functions</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/reference/functions/test" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Test SDK</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/functions/callable-reference" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Protocol specification for https.onCall</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/functions/video-series" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Video Series: learn Cloud Functions</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/functions/functions-and-firebase" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Cloud Functions and Firebase</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/functions/locations" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Cloud Functions locations</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/functions/quotas" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Quotas and limits</span></a></li></ul></devsite-expandable-nav></li> <li class="devsite-nav-item devsite-nav-expandable devsite-nav-accordion devsite-nav-beta"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Machine Learning</span><span class="devsite-nav-icon material-icons" data-icon="beta" data-title="Beta" aria-hidden="true"></span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Introduction</span></a></li><li class="devsite-nav-item devsite-nav-heading"><div class="devsite-nav-title devsite-nav-title-no-path"><span class="devsite-nav-text" tooltip>Vision</span></div></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Recognize text</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml/recognize-text" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Overview</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml/ios/recognize-text" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>iOS</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml/android/recognize-text" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Android</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Label images</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml/label-images" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Overview</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml/ios/label-images" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>iOS</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml/android/label-images" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Android</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Recognize landmarks</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml/recognize-landmarks" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Overview</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml/ios/recognize-landmarks" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>iOS</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml/android/recognize-landmarks" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Android</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-heading"><div class="devsite-nav-title devsite-nav-title-no-path"><span class="devsite-nav-text" tooltip>AutoML Vision Edge</span></div></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml/automl-image-labeling" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Overview</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml/train-image-labeler" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Train image labeling models</span></a></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Label images with your models</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml/ios/label-images-with-automl" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>iOS</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml/android/label-images-with-automl" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Android</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml/migrate-automl-datasets" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Migrate datasets</span></a></li><li class="devsite-nav-item devsite-nav-heading"><div class="devsite-nav-title devsite-nav-title-no-path"><span class="devsite-nav-text" tooltip>Custom Models</span></div></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Use a custom model</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml/use-custom-models" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Overview</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml/ios/use-custom-models" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>iOS</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml/android/use-custom-models" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Android</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml/manage-hosted-models" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Deploy &amp; manage custom models</span></a></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Migrate from the legacy API</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml/ios/migrate-from-legacy-api" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>iOS</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml/android/migrate-from-legacy-api" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Android</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-heading"><div class="devsite-nav-title devsite-nav-title-no-path"><span class="devsite-nav-text" tooltip>Advanced Topics</span></div></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>A/B test two versions of a model</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml/ios/ab-test-models" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>iOS</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml/android/ab-test-models" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Android</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-heading"><div class="devsite-nav-title devsite-nav-title-no-path"><span class="devsite-nav-text" tooltip>Prepare for Production</span></div></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Protect your Cloud credentials</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml/ios/secure-api-key" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>iOS</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml/android/secure-api-key" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Android</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-heading"><div class="devsite-nav-title devsite-nav-title-no-path"><span class="devsite-nav-text" tooltip>Legacy Documentation</span></div></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>ML Kit for Firebase</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Introduction</span></a></li><li class="devsite-nav-item devsite-nav-heading"><div class="devsite-nav-title devsite-nav-title-no-path"><span class="devsite-nav-text" tooltip>Vision</span></div></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Recognize text</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/recognize-text" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Overview</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/ios/recognize-text" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>iOS</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/android/recognize-text" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Android</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Detect faces</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/detect-faces" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Overview</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/face-detection-concepts" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Concepts</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/ios/detect-faces" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>iOS</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/android/detect-faces" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Android</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Scan barcodes</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/read-barcodes" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Overview</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/ios/read-barcodes" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>iOS</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/android/read-barcodes" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Android</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Label images</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/label-images" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Overview</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/ios/label-images" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>iOS</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/android/label-images" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Android</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Detect and track objects</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/object-detection" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Overview</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/ios/detect-objects" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>iOS</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/android/detect-objects" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Android</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Recognize landmarks</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/recognize-landmarks" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Overview</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/ios/recognize-landmarks" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>iOS</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/android/recognize-landmarks" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Android</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-heading"><div class="devsite-nav-title devsite-nav-title-no-path"><span class="devsite-nav-text" tooltip>AutoML Vision Edge</span></div></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/automl-image-labeling" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Overview</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/train-image-labeler" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Train image labeling models</span></a></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Label images with your models</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/ios/label-images-with-automl" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>iOS</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/android/label-images-with-automl" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Android</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/migrate-automl-datasets" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Migrate datasets</span></a></li><li class="devsite-nav-item devsite-nav-heading"><div class="devsite-nav-title devsite-nav-title-no-path"><span class="devsite-nav-text" tooltip>Natural Language</span></div></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Identify the language of text</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/identify-languages" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Overview</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/ios/identify-languages" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>iOS</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/android/identify-languages" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Android</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Translate text</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/translation" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Overview</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/ios/translate-text" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>iOS</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/android/translate-text" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Android</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/translation-terms" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Usage guidelines</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Generate smart replies</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/generate-smart-replies" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Overview</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/ios/generate-smart-replies" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>iOS</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/android/generate-smart-replies" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Android</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-heading"><div class="devsite-nav-title devsite-nav-title-no-path"><span class="devsite-nav-text" tooltip>Custom Models</span></div></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Use a custom model</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/use-custom-models" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Overview</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/ios/use-custom-models" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>iOS</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/android/use-custom-models" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Android</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/manage-hosted-models" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Manage hosted custom models</span></a></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Use a custom TensorFlow Lite build</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/ios/use-custom-tflite" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>iOS</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/android/use-custom-tflite" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Android</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-heading"><div class="devsite-nav-title devsite-nav-title-no-path"><span class="devsite-nav-text" tooltip>Advanced Topics</span></div></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>A/B test two versions of a model</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/ios/ab-test-models" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>iOS</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/android/ab-test-models" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Android</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-heading"><div class="devsite-nav-title devsite-nav-title-no-path"><span class="devsite-nav-text" tooltip>Prepare for Production</span></div></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Reduce app package size</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/android/reduce-app-size" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Android</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Protect your Cloud credentials</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/ios/secure-api-key" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>iOS</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ml-kit/android/secure-api-key" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Android</span></a></li></ul></devsite-expandable-nav></li></ul></devsite-expandable-nav></li></ul></devsite-expandable-nav></li> <li class="devsite-nav-item devsite-nav-expandable devsite-nav-accordion"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Security Rules</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/rules" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Introduction</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/rules/get-started" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get started</span></a></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Understand Security Rules</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/rules/rules-language" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Security Rules language</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/rules/rules-behavior" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>How Security Rules work</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/rules/rules-and-auth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Security Rules and Firebase Authentication</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Write Security Rules</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/rules/basics" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Basic Security Rules</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/rules/insecure-rules" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Avoid insecure rules</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/rules/data-validation" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Data validation</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Test Security Rules</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/rules/emulator-setup" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Set up the emulator</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/rules/unit-tests" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Build unit tests</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/rules/emulator-reports" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Generate test reports</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/rules/simulator" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Quickly validate Security Rules</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/rules/manage-deploy" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Manage and deploy Security Rules</span></a></li></ul></devsite-expandable-nav></li> <li class="devsite-nav-item devsite-nav-divider devsite-nav-heading"><div class="devsite-nav-title devsite-nav-title-no-path"><span class="devsite-nav-text" tooltip>Quality</span></div></li> <li class="devsite-nav-item devsite-nav-expandable devsite-nav-accordion"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Crashlytics</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/crashlytics" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Introduction</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/crashlytics/get-started" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get started</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/crashlytics/start-using-analytics" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get metrics with Google Analytics</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/crashlytics/test-implementation" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Test your implementation</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/crashlytics/customize-crash-reports" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Customize crash reports</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/crashlytics/get-deobfuscated-reports" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get deobfuscated crash reports</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/crashlytics/ndk-reports" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get Android NDK crash reports</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/crashlytics/velocity-alerts" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Customize velocity alerts</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/crashlytics/bigquery-export" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Export data to BigQuery</span></a></li><li class="devsite-nav-item devsite-nav-new"><a href="/web/20201022183222/https://firebase.google.com/docs/crashlytics/troubleshooting" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Troubleshooting</span><span class="devsite-nav-icon material-icons" data-icon="new" data-title="New!" aria-hidden="true"></span></a></li><li class="devsite-nav-item devsite-nav-heading"><div class="devsite-nav-title devsite-nav-title-no-path"><span class="devsite-nav-text" tooltip>From Fabric to Firebase</span></div></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/crashlytics/migration-post-linking" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Steps after migrating your app</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/crashlytics/upgrade-sdk" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Upgrade to the Firebase Crashlytics SDK</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/crashlytics/switch-to-analytics" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Switch from Answers to Analytics</span></a></li></ul></devsite-expandable-nav></li> <li class="devsite-nav-item devsite-nav-expandable devsite-nav-accordion"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Performance Monitoring</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/perf-mon" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Introduction</span></a></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Get started</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/perf-mon/get-started-ios" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>iOS</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/perf-mon/get-started-android" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Android</span></a></li><li class="devsite-nav-item devsite-nav-beta"><a href="/web/20201022183222/https://firebase.google.com/docs/perf-mon/get-started-web" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Web</span><span class="devsite-nav-icon material-icons" data-icon="beta" data-title="Beta" aria-hidden="true"></span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-heading"><div class="devsite-nav-title devsite-nav-title-no-path"><span class="devsite-nav-text" tooltip>Learn about automatically collected data</span></div></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/perf-mon/app-start-foreground-background-traces" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>App start, foreground, background (iOS &amp; Android)</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/perf-mon/screen-traces" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Screen rendering (iOS &amp; Android)</span></a></li><li class="devsite-nav-item devsite-nav-beta"><a href="/web/20201022183222/https://firebase.google.com/docs/perf-mon/page-load-traces" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Page loading (web)</span><span class="devsite-nav-icon material-icons" data-icon="beta" data-title="Beta" aria-hidden="true"></span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/perf-mon/network-traces" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>HTTP/S network requests</span></a></li><li class="devsite-nav-item devsite-nav-heading"><div class="devsite-nav-title devsite-nav-title-no-path"><span class="devsite-nav-text" tooltip>Customize data collection and aggregation</span></div></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/perf-mon/custom-code-traces" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Add monitoring for specific code</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/perf-mon/custom-network-traces" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Add monitoring for specific network requests</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/perf-mon/custom-url-patterns" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Create custom URL patterns</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/perf-mon/disable-sdk" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Disable Performance Monitoring</span></a></li><li class="devsite-nav-item devsite-nav-heading"><div class="devsite-nav-title devsite-nav-title-no-path"><span class="devsite-nav-text" tooltip>Track, view, and filter data</span></div></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/perf-mon/console" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Overview of the console</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/perf-mon/attributes" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Filter data using attributes</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/perf-mon/issue-management" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>View performance issues</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/perf-mon/bigquery-export" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Export data to BigQuery</span></a></li><li class="devsite-nav-item devsite-nav-break"></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/perf-mon/troubleshooting" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Troubleshooting</span></a></li></ul></devsite-expandable-nav></li> <li class="devsite-nav-item devsite-nav-expandable devsite-nav-accordion"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Test Lab</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/test-lab" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Introduction</span></a></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>iOS</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/test-lab/ios/firebase-console" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Test with the Firebase console</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/test-lab/ios/command-line" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Test with the gcloud CLI</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/test-lab/game-loop" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Run a Game Loop test</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/test-lab/ios/analyzing-results" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Analyze test results</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/test-lab/ios/available-testing-devices" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Test on available devices</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Android</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/test-lab/android/overview" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Overview</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/test-lab/android/firebase-console" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Test with the Firebase console</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/test-lab/android/command-line" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Test with the gcloud CLI</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/test-lab/android/continuous" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Test with CI systems</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/test-lab/android/android-studio" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Test with Android Studio</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/test-lab/android/analyzing-results" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Analyze test results</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/test-lab/android/available-testing-devices" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Test on available devices</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/test-lab/android/instrumentation-test" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Run an instrumentation test</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/test-lab/android/robo-ux-test" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Run a Robo test</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/test-lab/android/game-loop" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Run a Game Loop test</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/test-lab/android/test-screenshots" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Take screenshots in a test</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/test-lab/android/avds" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Test with virtual devices</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-new"><a href="/web/20201022183222/https://firebase.google.com/docs/test-lab/troubleshooting" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Troubleshooting</span><span class="devsite-nav-icon material-icons" data-icon="new" data-title="New!" aria-hidden="true"></span></a></li><li class="devsite-nav-item devsite-nav-new"><a href="/web/20201022183222/https://firebase.google.com/docs/test-lab/usage-quotas-pricing" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Usage, quotas, &amp; pricing</span><span class="devsite-nav-icon material-icons" data-icon="new" data-title="New!" aria-hidden="true"></span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/test-lab/extend-with-functions" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Extend with Cloud Functions</span></a></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>REST API reference</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/test-lab/reference/testing/rest" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Testing (submit test &amp; monitor)</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/test-lab/reference/toolresults/rest" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>ToolResults (retrieve results)</span></a></li></ul></devsite-expandable-nav></li></ul></devsite-expandable-nav></li> <li class="devsite-nav-item devsite-nav-expandable devsite-nav-accordion devsite-nav-beta"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>App Distribution</span><span class="devsite-nav-icon material-icons" data-icon="beta" data-title="Beta" aria-hidden="true"></span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/app-distribution" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Introduction</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/app-distribution/manage-testers" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Manage testers</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/app-distribution/troubleshooting" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Troubleshooting</span></a></li><li class="devsite-nav-item devsite-nav-heading"><div class="devsite-nav-title devsite-nav-title-no-path"><span class="devsite-nav-text" tooltip>Set up for testers</span></div></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/app-distribution/ios/set-up-for-testing" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>iOS</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/app-distribution/android/set-up-for-testing" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Android</span></a></li><li class="devsite-nav-item devsite-nav-heading"><div class="devsite-nav-title devsite-nav-title-no-path"><span class="devsite-nav-text" tooltip>Distribute iOS apps</span></div></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/app-distribution/ios/distribute-console" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Use the Firebase console</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/app-distribution/ios/distribute-cli" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Use the Firebase CLI</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/app-distribution/ios/distribute-fastlane" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Use fastlane</span></a></li><li class="devsite-nav-item devsite-nav-beta"><a href="/web/20201022183222/https://firebase.google.com/docs/app-distribution/set-up-alerts" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Set up in-app alerts</span><span class="devsite-nav-icon material-icons" data-icon="beta" data-title="Beta" aria-hidden="true"></span></a></li><li class="devsite-nav-item devsite-nav-heading"><div class="devsite-nav-title devsite-nav-title-no-path"><span class="devsite-nav-text" tooltip>Distribute Android apps</span></div></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/app-distribution/android/distribute-console" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Use the Firebase console</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/app-distribution/android/distribute-cli" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Use the Firebase CLI</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/app-distribution/android/distribute-fastlane" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Use fastlane</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/app-distribution/android/distribute-gradle" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Use Gradle</span></a></li></ul></devsite-expandable-nav></li> <li class="devsite-nav-item devsite-nav-divider devsite-nav-heading"><div class="devsite-nav-title devsite-nav-title-no-path"><span class="devsite-nav-text" tooltip>Grow</span></div></li> <li class="devsite-nav-item devsite-nav-expandable devsite-nav-accordion"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Predictions</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/predictions" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Introduction</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/predictions/get-started" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get started</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/predictions/predefined-predictions" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Churn and spend predictions</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/predictions/bigquery-export" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Export prediction data to BigQuery</span></a></li><li class="devsite-nav-item devsite-nav-heading"><div class="devsite-nav-title devsite-nav-title-no-path"><span class="devsite-nav-text" tooltip>Use case examples</span></div></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/predictions/use-cases/prevent-churn" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Prevent churn</span></a></li><li class="devsite-nav-item devsite-nav-break"></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Legacy Predictions (deprecated)</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/predictions/v1" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Introduction</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/predictions/v1/get-started" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get Started</span></a></li><li class="devsite-nav-item devsite-nav-heading"><div class="devsite-nav-title devsite-nav-title-no-path"><span class="devsite-nav-text" tooltip>Use Cases</span></div></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/predictions/use-cases/prevent-churn" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Prevent Churn</span></a></li><li class="devsite-nav-item devsite-nav-break"></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/predictions/v1/explore-predictions" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Explore Prediction Results</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/predictions/v1/bigquery-export" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Export Prediction Data to BigQuery</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/predictions/v1/predefined-predictions" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Churn and Spend Predictions</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/predictions/v1/risk-profiles" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Risk Tolerance and Model Performance</span></a></li></ul></devsite-expandable-nav></li></ul></devsite-expandable-nav></li> <li class="devsite-nav-item devsite-nav-expandable devsite-nav-accordion devsite-nav-beta"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>A/B Testing</span><span class="devsite-nav-icon material-icons" data-icon="beta" data-title="Beta" aria-hidden="true"></span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ab-testing" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Introduction</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ab-testing/abtest-config" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Create Remote Config Experiments with A/B Testing</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ab-testing/abtest-with-console" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Create Messaging Experiments with A/B Testing</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ab-testing/abtest-inappmessaging" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Create In-App Messaging Experiments with A/B Testing</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ab-testing/video-series" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Video Series: Learn A/B Testing</span></a></li></ul></devsite-expandable-nav></li> <li class="devsite-nav-item devsite-nav-expandable devsite-nav-accordion"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Cloud Messaging</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Introduction</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/fcm-architecture" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>FCM Architectural Overview</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/concept-options" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>About FCM messages</span></a></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>iOS</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/ios/client" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Set up an iOS client</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/ios/certs" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Configuring APNs with FCM</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/ios/first-message" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Send a test message</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/ios/send-multiple" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Send messages to multiple devices</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/ios/send-image" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Send an image in the notification payload</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/ios/receive" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Receive messages</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/ios/topic-messaging" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Send messages to topics</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/ios/device-group" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Send to device groups</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/ios/send-with-console" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Send messages with the Firebase Console</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Android</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/android/client" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Set up an Android client</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/android/first-message" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Send a test message</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/android/send-multiple" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Send messages to multiple devices</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/android/send-image" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Send an image in the notification payload</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/android/receive" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Receive messages</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/android/topic-messaging" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Send messages to topics</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/android/device-group" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Send to device groups</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/android/upstream" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Send upstream messages</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/android/send-with-console" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Send messages with the Firebase Console</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>C++</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/cpp/client" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Set up a C++ client</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/cpp/receive" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Receive messages</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/cpp/topic-messaging" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Send messages to topics</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/cpp/device-group" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Send to device groups</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/cpp/upstream" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Send upstream messages</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/cpp/send-with-console" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Send messages with the Firebase Console</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Unity</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/unity/client" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Set up a Unity client</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/unity/receive" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Receive messages</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/unity/topic-messaging" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Send messages to topics</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/unity/device-group" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Send to device groups</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/unity/upstream" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Send upstream messages</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/unity/send-with-console" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Send messages with the Firebase Console</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Web (JavaScript)</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/js/client" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Set up a JavaScript client</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/js/first-message" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Send a test message</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/js/send-multiple" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Send messages to multiple devices</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/js/receive" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Receive messages</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/js/topic-messaging" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Send messages to topics</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/js/device-group" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Send to device groups</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/js/send-with-console" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Send messages with the Firebase Console</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/js/case-studies" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Case studies</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Server environments</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/server" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Your server environment and FCM</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/migrate-v1" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Migrate to the HTTP v1 API</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/auth-server" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Authorize send requests</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/send-message" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Build send requests</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/receive-upstream" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Receive upstream messages</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/manage-topics" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Manage topics from the server</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/cloud-messaging/understand-delivery" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Understanding message delivery</span></a></li></ul></devsite-expandable-nav></li> <li class="devsite-nav-item devsite-nav-expandable devsite-nav-accordion devsite-nav-beta"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>In-App Messaging</span><span class="devsite-nav-icon material-icons" data-icon="beta" data-title="Beta" aria-hidden="true"></span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/in-app-messaging" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Introduction</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/in-app-messaging/get-started" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get started</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/in-app-messaging/explore-use-cases" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Explore use cases</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/in-app-messaging/compose-campaign" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Compose a campaign</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/in-app-messaging/modify-message-behavior" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Modify message behavior</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/in-app-messaging/customize-messages" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Customize messages</span></a></li></ul></devsite-expandable-nav></li> <li class="devsite-nav-item devsite-nav-expandable devsite-nav-accordion"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Remote Config</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/remote-config" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Introduction</span></a></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>What can I do with Remote Config?</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/remote-config/use-cases" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Remote Config use cases</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Key concepts and strategies</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/remote-config/parameters" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Parameters and conditions</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/remote-config/templates" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Templates and versioning</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/remote-config/loading" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Config loading strategies</span></a></li><li class="devsite-nav-item devsite-nav-beta"><a href="/web/20201022183222/https://firebase.google.com/docs/remote-config/propagate-updates-realtime" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Propagate updates in real time</span><span class="devsite-nav-icon material-icons" data-icon="beta" data-title="Beta" aria-hidden="true"></span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/remote-config/config-analytics" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Remote Config and Analytics</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>iOS</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/remote-config/use-config-ios" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get started with Remote Config on iOS</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Android</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/remote-config/use-config-android" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get started with Remote Config on Android</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Web (JavaScript)</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/remote-config/use-config-web" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get started with Remote Config on Web</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>C++</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/remote-config/use-config-cpp" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Use Remote Config with C++</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Unity</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/remote-config/use-config-unity" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Use Remote Config with Unity</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/remote-config/automate-rc" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Modify Remote Config programmatically</span></a></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>API reference</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/reference/remote-config/rest" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>REST API reference</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/remote-config/condition-reference" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Conditional expression reference</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/reference/android/com/google/firebase/remoteconfig/package-summary" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Android SDK reference</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/reference/swift/firebaseremoteconfig/api/reference/Classes" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>iOS Swift SDK reference</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/reference/ios/firebasecore/api/reference/Classes" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>iOS Obj-C SDK reference</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/reference/unity/namespace/firebase/remote-config" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Unity reference</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/reference/cpp/namespace/firebase/remote-config" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>C++ reference</span></a></li></ul></devsite-expandable-nav></li></ul></devsite-expandable-nav></li> <li class="devsite-nav-item devsite-nav-expandable devsite-nav-accordion"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Dynamic Links</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/dynamic-links" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Introduction</span></a></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Use Cases</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/dynamic-links/use-cases" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Overview</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/dynamic-links/use-cases/web-to-app" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Convert Web Users To App Users</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/dynamic-links/use-cases/user-to-user" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Invite Users to Your App</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/dynamic-links/use-cases/rewarded-referral" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Reward User Referrals</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/dynamic-links/operating-system-integrations" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Operating System Integrations</span></a></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Create Dynamic Links</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/dynamic-links/create-links" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Introduction</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/dynamic-links/ios/create" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>iOS</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/dynamic-links/android/create" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Android</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/dynamic-links/cpp/create" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>C++</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/dynamic-links/unity/create" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Unity</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/dynamic-links/rest" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>REST</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/dynamic-links/create-manually" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Manual URL Construction</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Receive Dynamic Links</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/dynamic-links/ios/receive" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>iOS</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/dynamic-links/android/receive" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Android</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/dynamic-links/cpp/receive" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>C++</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/dynamic-links/unity/receive" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Unity</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/dynamic-links/custom-domains" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Use a Custom Domain</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/dynamic-links/analytics" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>View Analytics Data</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/dynamic-links/debug" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Debug Dynamic Links</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/dynamic-links/link-previews" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Link Previews &amp; Social Metadata</span></a></li></ul></devsite-expandable-nav></li> <li class="devsite-nav-item devsite-nav-expandable devsite-nav-accordion"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Google AdMob</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/admob" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Introduction</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/admob/ios/quick-start" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get started for iOS</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/admob/android/quick-start" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get started for Android</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/admob/analytics-and-firebase" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Use Analytics and Firebase with AdMob apps</span></a></li><li class="devsite-nav-item devsite-nav-heading"><div class="devsite-nav-title devsite-nav-title-no-path"><span class="devsite-nav-text" tooltip>Use AdMob in a game</span></div></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>C++</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/admob/cpp/quick-start" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get started</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/admob/cpp/cocos2d-x" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Cocos2d-x</span></a></li><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/admob/cpp/rewarded-video" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Rewarded video</span></a></li></ul></devsite-expandable-nav></li><li class="devsite-nav-item devsite-nav-expandable"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Unity</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item devsite-nav-external"><a href="//web.archive.org/web/20201022183222/https://developers.google.com/admob/unity/start" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Get started</span><span class="devsite-nav-icon material-icons" data-icon="external" data-title="External" aria-hidden="true"></span></a></li></ul></devsite-expandable-nav></li></ul></devsite-expandable-nav></li> <li class="devsite-nav-item devsite-nav-expandable devsite-nav-accordion"><devsite-expandable-nav collapsed> <a class="devsite-nav-toggle" aria-hidden="true"></a><div class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Google Ads</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201022183222/https://firebase.google.com/docs/ads" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Introduction</span></a></li></ul></devsite-expandable-nav></li> <li class="devsite-nav-item devsite-nav-expandable 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left; } .full-page-selector-dropdown:hover .kd-buttonbar { border: none; height: inherit; } .full-page-selector-dropdown h3:hover { color: white; background-color: #039be5; } .full-page-selector-dropdown:hover .devsite-overflow-menu-button { display: none; } </style> <div class="devsite-banner devsite-banner-announcement"> <div class="devsite-banner-message"> <div class="devsite-banner-message-text"> <style> .devsite-banner-announcement:not(.devsite-banner-tenant) { background: #202124; color: white; font-weight: 500; } .devsite-banner-announcement a { color: white; font-weight: 700; } .devsite-banner-announcement a:link, .devsite-banner-announcement a:visited { background: 0; } .devsite-banner-announcement a:hover, .devsite-banner-announcement a:focus { text-decoration: none; } .devsite-banner-announcement .devsite-banner-message-text { margin: 0 auto; } </style> Google is committed to advancing racial equity for Black communities. <a href="https://web.archive.org/web/20201022183222/https://google.com/racialequity" class="gc-analytics-event" data-category="Announcement" data-label="Racial Equity">See how.</a> </div> </div> </div> <div class="devsite-article-meta"> <ul class="devsite-breadcrumb-list" role="navigation" aria-label="Breadcrumb"> <li class="devsite-breadcrumb-item "> <a href="/web/20201022183222/https://firebase.google.com/" class="devsite-breadcrumb-link gc-analytics-event" data-category="Site-Wide Custom Events" data-label="Breadcrumbs" data-value="1" track-type="globalNav" track-name="breadcrumb" track-metadata-position="1" track-metadata-eventdetail="Firebase"> Firebase </a> </li> <li class="devsite-breadcrumb-item "> <div class="devsite-breadcrumb-guillemet material-icons" aria-hidden="true"></div> <a href="/web/20201022183222/https://firebase.google.com/docs" class="devsite-breadcrumb-link gc-analytics-event" data-category="Site-Wide Custom Events" data-label="Breadcrumbs" data-value="2" track-type="globalNav" track-name="breadcrumb" track-metadata-position="2" track-metadata-eventdetail=""> Docs </a> </li> <li class="devsite-breadcrumb-item "> <div class="devsite-breadcrumb-guillemet material-icons" aria-hidden="true"></div> <a href="/web/20201022183222/https://firebase.google.com/docs/guides" class="devsite-breadcrumb-link gc-analytics-event" data-category="Site-Wide Custom Events" data-label="Breadcrumbs" data-value="3" track-type="globalNav" track-name="breadcrumb" track-metadata-position="3" track-metadata-eventdetail=""> Guides </a> </li> </ul> <devsite-page-rating position="header" selected-rating="0" hover-rating-star="0"> </devsite-page-rating> </div> <devsite-feedback position="header" project-name="Firebase" product-id="719752" bucket="" context="" version="t-devsite-webserver-20201015-r01-rc04.430365933905925364" data-label="Send Feedback Button" track-type="feedback" track-name="sendFeedbackLink" track-metadata-position="header" project-feedback-url="https://firebase.google.com/support/contact/bugs-features/" project-icon="https://firebase.google.com/_static/firebase/images/logo.png" project-support-url="https://firebase.google.com/support/"> <button> Send feedback </button> </devsite-feedback> <h1 class="devsite-page-title">Structure Your Database</h1> <devsite-toc class="devsite-nav" devsite-toc-embedded> </devsite-toc> <div class="devsite-article-body clearfix "> <p>This guide covers some of the key concepts in data architecture and best practices for structuring the JSON data in your Firebase Realtime Database.</p> <p>Building a properly structured database requires quite a bit of forethought. Most importantly, you need to plan for how data is going to be saved and later retrieved to make that process as easy as possible.</p> <h2 id="how_data_is_structured_its_a_json_tree" data-text="How data is structured: it's a JSON tree" tabindex="0">How data is structured: it's a JSON tree</h2> <p>All Firebase Realtime Database data is stored as JSON objects. You can think of the database as a cloud-hosted JSON tree. Unlike a SQL database, there are no tables or records. When you add data to the JSON tree, it becomes a node in the existing JSON structure with an associated key. You can provide your own keys, such as user IDs or semantic names, or they can be provided for you using the <a href="/web/20201022183222/https://firebase.google.com/docs/reference/rest/database#section-post"><code translate="no" dir="ltr">POST</code> request</a>.</p> <p class="note">If you create your own keys, they must be UTF-8 encoded, can be a maximum of 768 bytes, and cannot contain <code translate="no" dir="ltr">.</code>, <code translate="no" dir="ltr">$</code>, <code translate="no" dir="ltr">#</code>, <code translate="no" dir="ltr">[</code>, <code translate="no" dir="ltr">]</code>, <code translate="no" dir="ltr">/</code>, or ASCII control characters 0-31 or 127. You cannot use ASCII control characters in the values themselves, either. </p> <p>For example, consider a chat application that allows users to store a basic profile and contact list. A typical user profile is located at a path, such as <code translate="no" dir="ltr">/users/$uid</code>. The user <code translate="no" dir="ltr">alovelace</code> might have a database entry that looks something like this:</p> <pre class="prettyprint" translate="no" dir="ltr"> { "users": { "alovelace": { "name": "Ada Lovelace", "contacts": { "ghopper": true }, }, "ghopper": { ... }, "eclarke": { ... } } } </pre> <p>Although the database uses a JSON tree, data stored in the database can be represented as certain native types that correspond to available JSON types to help you write more maintainable code.</p> <h2 id="best_practices_for_data_structure" data-text="Best practices for data structure" tabindex="0">Best practices for data structure</h2> <h3 id="avoid_nesting_data" data-text="Avoid nesting data" tabindex="0">Avoid nesting data</h3> <p>Because the Firebase Realtime Database allows nesting data up to 32 levels deep, you might be tempted to think that this should be the default structure. However, when you fetch data at a location in your database, you also retrieve all of its child nodes. In addition, when you grant someone read or write access at a node in your database, you also grant them access to all data under that node. Therefore, in practice, it&#39;s best to keep your data structure as flat as possible.</p> <p>For an example of why nested data is bad, consider the following multiply-nested structure:</p> <pre class="prettyprint" translate="no" dir="ltr"> { // This is a poorly nested data architecture, because iterating the children // of the "chats" node to get a list of conversation titles requires // potentially downloading hundreds of megabytes of messages "chats": { "one": { "title": "Historical Tech Pioneers", "messages": { "m1": { "sender": "ghopper", "message": "Relay malfunction found. Cause: moth." }, "m2": { ... }, // a very long list of messages } }, "two": { ... } } } </pre> <p>With this nested design, iterating through the data becomes problematic. For example, listing the titles of chat conversations requires the entire <code translate="no" dir="ltr">chats</code> tree, including all members and messages, to be downloaded to the client.</p> <h3 id="flatten_data_structures" data-text="Flatten data structures" tabindex="0">Flatten data structures</h3> <p>If the data is instead split into separate paths, also called denormalization, it can be efficiently downloaded in separate calls, as it is needed. Consider this flattened structure:</p> <pre class="prettyprint" translate="no" dir="ltr"> { // Chats contains only meta info about each conversation // stored under the chats's unique ID "chats": { "one": { "title": "Historical Tech Pioneers", "lastMessage": "ghopper: Relay malfunction found. Cause: moth.", "timestamp": 1459361875666 }, "two": { ... }, "three": { ... } }, // Conversation members are easily accessible // and stored by chat conversation ID "members": { // we'll talk about indices like this below "one": { "ghopper": true, "alovelace": true, "eclarke": true }, "two": { ... }, "three": { ... } }, // Messages are separate from data we may want to iterate quickly // but still easily paginated and queried, and organized by chat // conversation ID "messages": { "one": { "m1": { "name": "eclarke", "message": "The relay seems to be malfunctioning.", "timestamp": 1459361875337 }, "m2": { ... }, "m3": { ... } }, "two": { ... }, "three": { ... } } } </pre> <p>It&#39;s now possible to iterate through the list of rooms by downloading only a few bytes per conversation, quickly fetching metadata for listing or displaying rooms in a UI. Messages can be fetched separately and displayed as they arrive, allowing the UI to stay responsive and fast.</p> <h3 id="fanout" data-text="Create data that scales" tabindex="0">Create data that scales</h3> <p>When building apps, it&#39;s often better to download a subset of a list. This is particularly common if the list contains thousands of records. When this relationship is static and one-directional, you can simply nest the child objects under the parent.</p> <p>Sometimes, this relationship is more dynamic, or it may be necessary to denormalize this data. Many times you can denormalize the data by using a query to retrieve a subset of the data, as discussed in <a href="/web/20201022183222/https://firebase.google.com/docs/database/rest/retrieve-data">Retrieve Data</a>.</p> <p>But even this may be insufficient. Consider, for example, a two-way relationship between users and groups. Users can belong to a group, and groups comprise a list of users. When it comes time to decide which groups a user belongs to, things get complicated.</p> <p>What&#39;s needed is an elegant way to list the groups a user belongs to and fetch only data for those groups. An <em>index</em> of groups can help a great deal here:</p> <pre class="prettyprint" translate="no" dir="ltr"> // An index to track Ada's memberships { "users": { "alovelace": { "name": "Ada Lovelace", // Index Ada's groups in her profile "groups": { // the value here doesn't matter, just that the key exists "techpioneers": true, "womentechmakers": true } }, ... }, "groups": { "techpioneers": { "name": "Historical Tech Pioneers", "members": { "alovelace": true, "ghopper": true, "eclarke": true } }, ... } } </pre> <p>You might notice that this duplicates some data by storing the relationship under both Ada&#39;s record and under the group. Now <code translate="no" dir="ltr">alovelace</code> is indexed under a group, and <code translate="no" dir="ltr">techpioneers</code> is listed in Ada&#39;s profile. So to delete Ada from the group, it has to be updated in two places.</p> <p>This is a necessary redundancy for two-way relationships. It allows you to quickly and efficiently fetch Ada&#39;s memberships, even when the list of users or groups scales into the millions or when Realtime Database security rules prevent access to some of the records.</p> <p>This approach, inverting the data by listing the IDs as keys and setting the value to true, makes checking for a key as simple as reading <code translate="no" dir="ltr">/users/$uid/groups/$group_id</code> and checking if it is <code translate="no" dir="ltr">null</code>. 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