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class="devsite-nav-title devsite-nav-title-no-path" tabindex="0" role="button"><span class="devsite-nav-text" tooltip>Add Firebase to an app</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201114231845/https://firebase.google.com/docs/ios/setup" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>iOS</span></a></li><li class="devsite-nav-item"><a href="/web/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/https://firebase.google.com/docs/projects/api-keys" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Learn about API keys for Firebase</span></a></li><li class="devsite-nav-item"><a href="/web/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/https://firebase.google.com/docs/projects/iam/roles-basic" 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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/https://firebase.google.com/docs/emulator-suite/connect_auth" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Connect to the Authentication emulator</span></a></li><li class="devsite-nav-item"><a href="/web/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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 & Rules</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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 & Rules</span></div><ul class="devsite-nav-section"><li class="devsite-nav-item"><a href="/web/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/https://firebase.google.com/docs/hosting/manage-hosting-resources" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Manage live & preview channels, releases, and versions</span></a></li><li class="devsite-nav-item devsite-nav-new"><a href="/web/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/https://firebase.google.com/docs/functions/tips" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Tips & 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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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"><a href="/web/20201114231845/https://firebase.google.com/docs/ml/codelabs" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Codelabs</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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/https://firebase.google.com/docs/ml/manage-hosted-models" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Deploy & 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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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 & Android)</span></a></li><li class="devsite-nav-item"><a href="/web/20201114231845/https://firebase.google.com/docs/perf-mon/screen-traces" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Screen rendering (iOS & Android)</span></a></li><li class="devsite-nav-item devsite-nav-beta"><a href="/web/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/https://firebase.google.com/docs/test-lab/usage-quotas-pricing" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Usage, quotas, & 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/20201114231845/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/20201114231845/https://firebase.google.com/docs/test-lab/reference/testing/rest" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Testing (submit test & monitor)</span></a></li><li class="devsite-nav-item"><a href="/web/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/https://firebase.google.com/docs/dynamic-links/link-previews" class="devsite-nav-title"><span class="devsite-nav-text" tooltip>Link Previews & 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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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/20201114231845/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 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href="https://web.archive.org/web/20201114231845/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="https://web.archive.org/web/20201114231845/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="https://web.archive.org/web/20201114231845/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="https://web.archive.org/web/20201114231845/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-20201105-r00-rc03.430844314467022312" 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">Transaction serializability and isolation</h1> <devsite-toc class="devsite-nav" devsite-toc-embedded> </devsite-toc> <div class="devsite-article-body clearfix "> <p>This page describes transactional data contention, serializability, and isolation. For transaction code samples, see <a href="https://web.archive.org/web/20201114231845/https://firebase.google.com/docs/firestore/manage-data/transactions">transactions and batched writes</a> instead.</p> <h2 id="transactions_and_data_contention" data-text="Transactions and data contention" tabindex="0">Transactions and data contention</h2> <p>For a transaction to succeed, the documents retrieved by its read operations must remain unmodified by operations outside the transaction. If another operation attempts to change one of those documents, that operations enters a state of data contention with the transaction.</p> <dl> <dt>Data contention</dt> <dd>When two or more operations compete to control the same document. For example, one transaction might require a document to remain consistent while a concurrent operation tries to update that document's field values.</dd> </dl> <p>Cloud Firestore resolves data contention by delaying or failing one of the operations. The Cloud Firestore client libraries automatically retry transactions that fail due to data contention. After a finite number of retries, the transaction operation fails and returns an error message:</p> <pre class="prettyprint" translate="no" dir="ltr"><code translate="no" dir="ltr">ABORTED: Too much contention on these documents. Please try again. </code></pre> <p><span id="concurrency-controls"></span></p> <p>When deciding which operation to fail or delay, behavior depends the type of client library.</p> <ul> <li><p>The mobile/web SDKs use optimistic concurrency controls.</p></li> <li><p>The server client libraries use pessimistic concurrency controls.</p></li> </ul> <aside class="key-term"><strong>Key Term:</strong><span> In database systems, <em>concurrency controls</em> describe how the system resolves data contention between concurrent operations. Systems can implement optimistic or pessimistic concurrency controls.</span></aside> <h3 id="data_contention_in_the_mobileweb_sdks" data-text="Data contention in the mobile/web SDKs" tabindex="0">Data contention in the mobile/web SDKs</h3> <p>The mobile/web SDKs (iOS, Android, Web, C++) use optimistic concurrency controls to resolve data contention.</p> <dl> <dt>Optimistic concurrency controls</dt> <dd>Based on the assumption that data contention is not likely or that it's not efficient to hold database locks. Optimistic transactions do not use database locks to block other other operations from changing data.</dd> </dl> <p>Mobile/web SDKs use optimistic concurrency controls, because they can operate in environments with high latency and an unreliable network connection. Locking documents in a high latency environment would cause too many data contention failures.</p> <p>In the Mobile/Web SDKs, a transaction keeps track of all the documents you read inside the transaction. The transaction completes its write operations <strong>only if</strong> none of those documents changed during the transaction's execution. If any document did change, the transaction handler retries the transaction. If the transaction can't get a clean result after a few retries, the transaction fails due to data contention.</p> <h3 id="data_contention_in_the_server_client_libraries" data-text="Data contention in the server client libraries" tabindex="0">Data contention in the server client libraries</h3> <p>The server client libraries (C#, Go, Java, Node.js, PHP, Python, Ruby) use pessimistic concurrency controls resolve data contention.</p> <dl> <dt>Pessimistic concurrency controls</dt> <dd>Based on the assumption that data contention is likely. Pessimistic transactions use database locks to prevent other operations from modifying data.</dd> </dl> <p>Server client libraries use pessimistic concurrency controls, because they assume low latency and a reliable connection to the database.</p> <aside class="note"><strong>Note:</strong><span> To best ensure low latency, use server client libraries from a <a href="https://web.archive.org/web/20201114231845/https://cloud.google.com/about/locations#products-available-by-location">Google Cloud Platform compute product as close to your Cloud Firestore database as possible</a>. A server client library with a high latency connection can run into issues with locking and data contention.</span></aside> <p>In the server client libraries, transactions place locks on the documents they read. A transaction's lock on a document blocks other transactions, batched writes, and non-transactional writes from changing that document. A transaction releases its document locks at commit time. It also releases its locks if it times out or fails for any reason.</p> <p>When a transaction locks a document, other write operations must wait for the transaction to release its lock. Transactions acquire their locks in chronological order.</p> <h2 id="serializable_isolation" data-text="Serializable isolation" tabindex="0">Serializable isolation</h2> <p>Data contention between transactions is closely related to database isolation levels. A database's <em>isolation level</em> describes how well the system handles conflicts between concurrent operations. Conflict comes from the following database requirements:</p> <ul> <li>Transactions require accurate, consistent data.</li> <li>To efficiently use resources, databases execute operations concurrently.</li> </ul> <p>In systems with a low isolation level, a read operation within a transaction might read inaccurate data from uncommitted changes in a concurrent operation.</p> <p><em>Serializable isolation</em> defines the highest isolation level. Serializable isolation means that:</p> <ul> <li>You can assume that the database executes transactions in series.</li> <li>Transactions are not affected by uncommitted changes in concurrent operations.</li> </ul> <p>This guarantee must hold even while the database executes multiple transactions in parallel. The database must implement concurrency controls to resolve conflicts that would break this guarantee.</p> <p>Cloud Firestore guarantees serializable isolation of transactions. Transactions in Cloud Firestore are serialized and isolated by commit time.</p> <h3 id="serializable_isolation_by_commit_time" data-text="Serializable isolation by commit time" tabindex="0">Serializable isolation by commit time</h3> <p>Cloud Firestore assigns each transaction a commit time which represents a single point in time. When Cloud Firestore commits a transaction's changes to the database, you can assume all reads and writes within the transaction take place exactly at the commit time.</p> <p>Actual execution of a transaction requires some span of time. The execution of a transaction begins before the commit time, and the execution of multiple operations may overlap. Cloud Firestore upholds serializable isolation and guarantees that:</p> <ul> <li>Cloud Firestore commits transactions in order by commit time.</li> <li>Cloud Firestore isolates transactions from concurrent operations with a later commit time.</li> </ul> <p>In the case of data contention between concurrent operations, <a href="#concurrency-controls">Cloud Firestore uses optimistic and pessimistic concurrency controls to resolve contention.</a></p> <h3 id="isolation_within_a_transaction" data-text="Isolation within a transaction" tabindex="0">Isolation within a transaction</h3> <p>Transaction isolation also applies to write operations within a transaction. Queries and reads inside a transaction do not see the results of previous writes inside that transaction. Even if you modify or delete a document within a transaction, all document reads in that transaction return the version of the document at commit time, before the transaction's write operations. Read operations return nothing if the document did not exist then.</p> <aside class="note"><strong>Note:</strong><span> Only the server client libraries support transactions with read operations after write operations. 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