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-moz-osx-font-smoothing: grayscale; } .swiper-button{ -webkit-mask-image: -webkit-radial-gradient(white, black); } </style> <style> /* Style the custom checkbox */ .hs-input[type="checkbox"] { box-sizing: border-box; display: none; /* Hide the default checkbox */ } /* Hide the marker for list items with the class 'hs-form-booleancheckbox' */ li.hs-form-booleancheckbox::marker { display: none; content: none; } div.hbspt-form ul.inputs-list { padding-left: 0; } /* Style the custom checkbox container */ .hs-form-booleancheckbox-display { position: relative; padding-left: 24px; /* Adjust as needed */ cursor: pointer; margin-top: 8px; /* Add margin top */ margin-left: 0; /* Adjust margin to remove space taken by the marker */ } /* Create the custom checkbox design */ .hs-form-booleancheckbox-display::before { box-sizing: border-box; content: ""; position: absolute; left: 0; top: 50%; transform: translate(0%,-50%); width: 16px; /* Adjust the size as needed */ height: 16px; /* Adjust the size as needed */ border: 2px solid #19E632; /* Green border for the checkbox */ background-color: transparent !important; border-radius: 100%; /* Make it fully rounded */ } /* Style the checkmark when the checkbox is checked */ .checkbox-checked{ background-color: #19E632; /* Fill color when checked */ border: 1px solid #19E632; /* Ensure the border stays the same */ border-radius: 50%; /* Make it fully rounded */ box-sizing: border-box; content: ""; position: absolute; left: 0; top: 50%; transform: translate(0%,-50%); width: 16px; /* Adjust the size as needed */ height: 16px; /* Adjust the size as needed */ } </style> <style> /* ----------- GENERAL RULES HubSpot ----------- */ .get-in-touch-form label { color: #fff; } .footer-newsletter-embed label { color: #FF1E73 !important; } .footer-newsletter-embed input[type="email"] { color: #000 !important; /* Set text color to black */ } .hs-input.invalid.error { border: 2px solid #FF1E73 !important; } label.hs-error-msg.hs-main-font-element { 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.hs-button { background-color: var(--colours-main--green); color: var(--colours-main--navy); cursor: pointer; border-radius: 1.9375rem; flex: 0 auto; justify-content: center; align-items: center; padding: 1rem 1.5rem; font-family: Inter, sans-serif; font-size: 1rem; font-weight: 600; text-decoration: none; transition-property: none; display: inline-block; border: none !important; width: 100%; } .footer-newsletter-embed .hs-button { width: auto; padding: .75rem 1.5rem; } .hs-button:hover { background-image: linear-gradient(180deg, var(--colours-secondary--warning), var(--colours-main--green)); } } </style> <style> .dropdown-list-backgroud { pointer-events: none; } .secondary-button-dark-small{ -webkit-mask-image: -webkit-radial-gradient(white, black); } .secondary-button-dark-big{ -webkit-mask-image: -webkit-radial-gradient(white, black); } .primary-button-big{ -webkit-mask-image: -webkit-radial-gradient(white, black); } .primary-button-small{ -webkit-mask-image: -webkit-radial-gradient(white, black); } .services-item { -webkit-mask-image: -webkit-radial-gradient(white, black); } </style> <style> /* Set default opacity to 0 for elements with the data-opacity attribute */ [data-opacity] { opacity: 0; transition: opacity 0.5s; /* Add a transition for a smooth effect */ } </style> <style> /* Rich text element style for Bold in Quote*/ .rich-text-element blockquote strong { font-weight: 400 !important; font-size: 0.875rem !important; height: 160% !important; } </style> <style> /* fix flash of unwanted content */ body { opacity: 0; transition: opacity 0.1s ease-in-out; } body.loaded { opacity: 1; } </style> <style> .legal-consent-container p { font-family: Inter, sans-serif; font-size: .625rem; font-weight: 400; line-height: 1.5em; color: var(--colours-secondary--neutral-white); margin-top: 1.5rem; } </style> <style> .nice-select span{ position: absolute; max-width: 90%; overflow: auto; } @media (max-width: 991px) { .nice-select span{ max-width: 88%; } } @media (max-width: 585px) { .nice-select span{ max-width: 82%; } } .nice-select span::-webkit-scrollbar { display: none; } .nice-select span { -ms-overflow-style: none; /* IE and Edge */ scrollbar-width: none; /* Firefox */ } </style></head><body><div data-animation="default" class="navigation w-nav" data-easing2="ease" data-wf--navigation-redesign--variant="base" data-easing="ease" data-collapse="medium" data-w-id="6491e0d8-fc91-68ee-1706-332d22f88a18" role="banner" data-duration="400"><div class="nav-opacity"></div><div class="nav-bg-fix"></div><div class="nav-container"><a href="/" aria-current="page" class="nav-brand w-nav-brand w--current"><img sizes="(max-width: 479px) 96vw, 235.203125px" srcset="https://cdn.prod.website-files.com/64d0b1ecf0fc228ea4057bb5/64d1ffc562b0e865fabcda52_Vector%20(1)-p-500.webp 500w, https://cdn.prod.website-files.com/64d0b1ecf0fc228ea4057bb5/64d1ffc562b0e865fabcda52_Vector%20(1).webp 1738w" alt="Callstack Logo" src="https://cdn.prod.website-files.com/64d0b1ecf0fc228ea4057bb5/64d1ffc562b0e865fabcda52_Vector%20(1).webp" loading="lazy" class="nav-logo"/></a><nav role="navigation" class="nav-menu nav-menu-rebrand w-nav-menu"><div class="nav-menu-mask-rebrand"><div data-delay="0" data-hover="true" data-w-id="6491e0d8-fc91-68ee-1706-332d22f88a20" class="nav-dropdown nav-about-dropdown w-dropdown"><div data-w-id="6491e0d8-fc91-68ee-1706-332d22f88a21" class="nav-dropdown-toggle nav-dropdown-rebrand w-dropdown-toggle"><a href="/about-us" class="nav-dropdown-link w-inline-block"><div class="hide">.</div></a><div class="is-txt-small is-txt-medium">About us</div><div class="nav-dropdown-arrow w-embed"><svg width="100%" height="100%" viewBox="0 0 11 8" fill="none" xmlns="http://www.w3.org/2000/svg"> <path d="M9.99992 1.44922L5.84163 5.77457L1.68335 1.44922" stroke="currentColor" stroke-width="2" stroke-linecap="round"/> </svg></div></div><nav class="nav-dropdown-list nav-about-dropdown-list w-dropdown-list"><div class="nav-dropdown-list-wrapper"><div class="is-container is-grid nav-container"><div id="w-node-_9dcf6c75-67a1-faf9-392f-2f4057f55063-22f88a18" class="is-column navigation-left-column-link"><a id="w-node-_9dcf6c75-67a1-faf9-392f-2f4057f55064-22f88a18" href="/about-us" class="is-nav-link is-t-hidden is-txt-offwhite">About us</a><a href="/about-us" class="btn-sec--stroke is-full-width-mobile is-d-hidden is-t-visible w-button">Explore all about us</a><div class="navigation-left-column-hl"></div><div class="navigation-left-column-link-about-us"><div id="w-node-_64e14513-eefa-8003-5684-bcdb193971f0-22f88a18" class="navigation-left-column-link-wrapper"><a id="w-node-_64e14513-eefa-8003-5684-bcdb193971f1-22f88a18" href="/careers" class="is-nav-link is-txt-offwhite">Careers</a><img src="https://cdn.prod.website-files.com/64d0b1ecf0fc228ea4057bb5/66559c352bf2085d630df714_Down%20Arrow%202.svg" loading="lazy" alt="" class="navigation-left-column-arrow"/></div><div id="w-node-_9dcf6c75-67a1-faf9-392f-2f4057f55072-22f88a18" class="navigation-left-column-link-wrapper"><a id="w-node-_9dcf6c75-67a1-faf9-392f-2f4057f55073-22f88a18" href="/referral-program" class="is-nav-link is-txt-offwhite">Referral program</a><img src="https://cdn.prod.website-files.com/64d0b1ecf0fc228ea4057bb5/66559c352bf2085d630df714_Down%20Arrow%202.svg" loading="lazy" alt="" class="navigation-left-column-arrow"/></div><div class="navigation-left-column-link-wrapper"><a id="w-node-_9dcf6c75-67a1-faf9-392f-2f4057f5506b-22f88a18" href="/team" class="is-nav-link is-txt-offwhite">Team</a><img src="https://cdn.prod.website-files.com/64d0b1ecf0fc228ea4057bb5/66559c352bf2085d630df714_Down%20Arrow%202.svg" loading="lazy" alt="" class="navigation-left-column-arrow"/></div></div></div><div id="w-node-_9dcf6c75-67a1-faf9-392f-2f4057f55082-22f88a18" class="is-column is-txt-offwhite is-t-hidden"><p class="is-sub-small is-margin-b-24">" Joining Callstack, I was excited, mostly because of one thing - I was going to work with experts who built open-source tools that I've been using in my projects...”</p><div class="is-row-l-h-b-12"><img src="https://cdn.prod.website-files.com/64d0b1ecf0fc228ea4057bb5/665849b5fba88ae33874f088_personimage.png" loading="lazy" alt="" class="nav-about-image"/><div class="is-column"><p class="is-txt-small">Jakub Urban</p><p class="is-txt-small">Senior Software Engineer</p></div></div></div></div></div></nav></div><a href="/technology" class="nav-case-link nav-dropdown-rebrand is-txt-small is-txt-medium">Technology</a><div data-delay="0" data-hover="true" class="nav-dropdown nav-services-dropdown w-dropdown"><div id="service-dropdown" class="nav-dropdown-toggle nav-dropdown-rebrand w-dropdown-toggle"><a href="/services" class="nav-dropdown-link w-inline-block"><div class="hide">.</div></a><div class="is-txt-small is-txt-medium">Services</div><div class="nav-dropdown-arrow w-embed"><svg width="100%" height="100%" viewBox="0 0 11 8" fill="none" xmlns="http://www.w3.org/2000/svg"> <path d="M9.99992 1.44922L5.84163 5.77457L1.68335 1.44922" stroke="currentColor" stroke-width="2" stroke-linecap="round"/> </svg></div></div><nav class="nav-dropdown-list nav-services-dropdown-list-redesign w-dropdown-list"><div class="nav-dropdown-list-wrapper"><div class="is-container is-grid"><div id="w-node-ebb65425-2f49-ac9a-8614-8cc17f7adec5-22f88a18" class="is-column nav-services-main"><a id="w-node-ebb65425-2f49-ac9a-8614-8cc17f7adec6-22f88a18" href="/services" class="is-nav-link is-t-hidden is-txt-offwhite">Explore all services</a><a href="/services" class="btn-sec--stroke is-full-width-mobile is-d-hidden is-t-visible is-margin-b-16 w-button">Explore all services</a><div class="navigation-left-column-hl"></div></div><div id="w-node-ebb65425-2f49-ac9a-8614-8cc17f7adecb-22f88a18" data-current="Product Development and Growth" data-easing="ease" data-duration-in="300" data-duration-out="100" class="is-container is-grid nav-container-services w-tabs"><div id="w-node-ebb65425-2f49-ac9a-8614-8cc17f7adecc-22f88a18" class="nav-tabs-wrapper-main w-tab-menu"><a data-w-tab="Product Development and Growth" data-w-id="ebb65425-2f49-ac9a-8614-8cc17f7adecd" class="nav-tab-link services-new w-inline-block w-tab-link w--current"><div class="nav-arrow-wrapper-bg"><div class="is-nav-link-services-tab">Product Development and Growth</div><div class="nav-dropdown-holder-arrow services w-embed"><svg width="11" height="8" viewBox="0 0 11 8" fill="none" xmlns="http://www.w3.org/2000/svg"> <path d="M9.99992 1.44922L5.84163 5.77457L1.68335 1.44922" stroke="currentColor" stroke-width="2" stroke-linecap="round"/> </svg></div></div></a><a data-w-tab="Optimization of Products and Processes" data-w-id="ebb65425-2f49-ac9a-8614-8cc17f7aded2" class="nav-tab-link services-new w-inline-block w-tab-link"><div class="nav-arrow-wrapper services"><div class="is-nav-link-services-tab">Optimization of Products and Processes</div><div class="nav-dropdown-holder-arrow services w-embed"><svg width="11" height="8" viewBox="0 0 11 8" fill="none" xmlns="http://www.w3.org/2000/svg"> <path d="M9.99992 1.44922L5.84163 5.77457L1.68335 1.44922" stroke="currentColor" stroke-width="2" stroke-linecap="round"/> </svg></div></div></a><a data-w-tab="Tech Stack Upgrade" data-w-id="ebb65425-2f49-ac9a-8614-8cc17f7aded7" class="nav-tab-link services-new w-inline-block w-tab-link"><div class="nav-arrow-wrapper services"><div class="is-nav-link-services-tab">Tech Stack Upgrade</div><div class="nav-dropdown-holder-arrow services w-embed"><svg width="11" height="8" viewBox="0 0 11 8" fill="none" xmlns="http://www.w3.org/2000/svg"> <path d="M9.99992 1.44922L5.84163 5.77457L1.68335 1.44922" stroke="currentColor" stroke-width="2" stroke-linecap="round"/> </svg></div></div></a><a data-w-tab="Team Upskilling" data-w-id="ebb65425-2f49-ac9a-8614-8cc17f7adedc" class="nav-tab-link services-new w-inline-block w-tab-link"><div class="nav-arrow-wrapper services"><div class="is-nav-link-services-tab">Team Upskilling</div><div class="nav-dropdown-holder-arrow services w-embed"><svg width="11" height="8" viewBox="0 0 11 8" fill="none" xmlns="http://www.w3.org/2000/svg"> <path d="M9.99992 1.44922L5.84163 5.77457L1.68335 1.44922" stroke="currentColor" stroke-width="2" stroke-linecap="round"/> </svg></div></div></a><a data-w-tab="Business Transformation" data-w-id="ebb65425-2f49-ac9a-8614-8cc17f7adee1" class="nav-tab-link services-new w-inline-block w-tab-link"><div class="nav-arrow-wrapper services"><div class="is-nav-link-services-tab">Business Transformation</div><div class="nav-dropdown-holder-arrow services w-embed"><svg width="11" height="8" viewBox="0 0 11 8" fill="none" xmlns="http://www.w3.org/2000/svg"> <path d="M9.99992 1.44922L5.84163 5.77457L1.68335 1.44922" stroke="currentColor" stroke-width="2" stroke-linecap="round"/> </svg></div></div></a></div><div 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src="https://cdn.prod.website-files.com/64d4ce10600bd67e51c42838/66746415572baf9ff16693e5_pwc.png" class="our-clients-logo"/></div><div role="listitem" class="our-clients-redesign-item w-dyn-item"><img alt="Auto Zone " loading="lazy" src="https://cdn.prod.website-files.com/64d4ce10600bd67e51c42838/667464827bd7b059e62fc59f_autozone.png" class="our-clients-logo"/></div><div role="listitem" class="our-clients-redesign-item w-dyn-item"><img alt="MLS" loading="lazy" src="https://cdn.prod.website-files.com/64d4ce10600bd67e51c42838/667464494aab38c299fcdbec_mls.png" class="our-clients-logo"/></div><div role="listitem" class="our-clients-redesign-item w-dyn-item"><img alt="Entain " loading="lazy" src="https://cdn.prod.website-files.com/64d4ce10600bd67e51c42838/6674645b13e4638fe223e084_entain.png" class="our-clients-logo"/></div><div role="listitem" class="our-clients-redesign-item w-dyn-item"><img alt="Ticketmaster" loading="lazy" src="https://cdn.prod.website-files.com/64d4ce10600bd67e51c42838/664dbb57c2e40efef086781b_TicketMaster.svg" class="our-clients-logo"/></div><div role="listitem" class="our-clients-redesign-item w-dyn-item"><img alt="Dream 11 " loading="lazy" src="https://cdn.prod.website-files.com/64d4ce10600bd67e51c42838/664dbb738a030cbb53db442b_amazon.svg" class="our-clients-logo"/></div></div></div><div id="w-node-f14cb5ab-1360-39f8-25eb-c01a985ad27f-85bc6e59" class="btn-property"><a href="/case-studies" class="btn-sec--dark w-button">See all case studies</a></div></div></div></section><section id="react-universe-section" class="is-section is-bg-purple hide"><div class="is-container is-grid"><div id="w-node-_9c003888-73df-378e-051e-2da7c785f88d-a4057bf2" class="wrap-flex-vert-l-c is-txt-offwhite"><h2 class="is-h1 is-margin-b-24">run your business on REACT UNIVERSE</h2><p class="is-sub-large is-margin-b-24">React Universe combines front and back-end development with cross-platform capabilities using a single programming model to make faster, better apps.</p><div class="is-btn-wrap-c-mob"><a href="/technology" class="btn-sec--stroke w-button">Dive deep into React Universe</a></div></div><a aria-label="react universe diagram" id="w-node-fda04a95-0e7d-744c-ea99-e3b36acba2b9-a4057bf2" href="/technology" class="w-inline-block"><div id="w-node-_9c003888-73df-378e-051e-2da7c785f895-a4057bf2" class="diagram-lottie-home" data-w-id="9c003888-73df-378e-051e-2da7c785f895" data-animation-type="lottie" data-src="https://cdn.prod.website-files.com/64d0b1ecf0fc228ea4057bb5/655dfbd9a929ce2806a23260_HomepageDotLottie.lottie" data-loop="1" data-direction="1" data-autoplay="1" data-is-ix2-target="0" data-renderer="svg" data-default-duration="15" data-duration="0"></div></a></div></section><section class="is-section is-bg-purple is-radius-t-80"><div class="is-container is-grid"><div id="w-node-ff87ab30-6a9d-2955-8a6d-bd4707c2034f-a4057bf2" class="wrap-flex-vert-l-c is-txt-offwhite"><h2 class="is-h1 is-margin-b-24">run your business on REACT UNIVERSE</h2><p class="is-sub-large is-margin-b-24">React Universe combines front and back-end development with cross-platform capabilities using a single programming model to make faster, better apps.</p><div class="is-btn-wrap-c-mob"><a href="/technology" class="btn-sec--stroke w-button">Dive deep into React Universe</a></div></div><div id="lottie-container" class="downloads-hero-lottie w-node-ff87ab30-6a9d-2955-8a6d-bd4707c20357-a4057bf2"><div id="w-node-ff87ab30-6a9d-2955-8a6d-bd4707c20358-a4057bf2" class="diagram-lottie-home full-height w-embed w-script"><div class="downloads-hero-lottie" id="lottie-container"></div> <script src="https://cdnjs.cloudflare.com/ajax/libs/bodymovin/5.7.4/lottie.min.js"></script> <script> document.addEventListener("DOMContentLoaded", function () { // Initialize Lottie var animation = lottie.loadAnimation({ container: document.getElementById("lottie-container"), // Container ID renderer: "svg", loop: true, // Loop settings autoplay: true, // Autoplay settings path: "https://cdn.prod.website-files.com/64d0b1ecf0fc228ea4057bb5/6532a4be6c18458a50794c99_callstack_1%20(2).json", // Animation path }); if (window.innerWidth >= 992) { // Select the container for hover events const lottieContainer = document.getElementById("lottie-container"); // Pause the animation on mouse hover lottieContainer.addEventListener('mouseenter', function () { animation.pause(); // Pause the animation }); // Resume the animation on mouse hover out lottieContainer.addEventListener('mouseleave', function () { animation.play(); // Resume the animation }); }; }); </script></div></div></div></section><section class="is-section is-bg-purple is-txt-offwhite is-relative is-radius-b-80"><img src="https://cdn.prod.website-files.com/64d0b1ecf0fc228ea4057bb5/665d8540c6f5eb6ebe52fd0c_chmurki%202.png" loading="lazy" sizes="(max-width: 1664px) 100vw, 1664px" srcset="https://cdn.prod.website-files.com/64d0b1ecf0fc228ea4057bb5/665d8540c6f5eb6ebe52fd0c_chmurki%202-p-500.webp 500w, https://cdn.prod.website-files.com/64d0b1ecf0fc228ea4057bb5/665d8540c6f5eb6ebe52fd0c_chmurki%202-p-800.webp 800w, https://cdn.prod.website-files.com/64d0b1ecf0fc228ea4057bb5/665d8540c6f5eb6ebe52fd0c_chmurki%202-p-1080.webp 1080w, https://cdn.prod.website-files.com/64d0b1ecf0fc228ea4057bb5/665d8540c6f5eb6ebe52fd0c_chmurki%202.png 1664w" alt="" class="universe-of-possibilities-image"/><div class="is-container is-grid"><div id="w-node-_9c003888-73df-378e-051e-2da7c785f899-a4057bf2" class="is-txt-align-center"><h2 class="is-h1 is-margin-b-24">a UNIVERSE of possibilities</h2><p class="is-sub-large is-margin-b-80">Instead of splitting development across multiple languages, platforms, and teams,we use the React Universe tech stack to make app development:</p></div><div id="w-node-_9c003888-73df-378e-051e-2da7c785f89e-a4057bf2" class="is-row-l-h-c-32 is-margin-b-40"><p class="is-display is-l-hidden">faster</p><div class="is-column is-max-w-350"><p class="is-h3 is-margin-b-16"><span class="is-hidden is-l-visible-inline">faster </span>with Fullstack</p><p class="is-sub-medium">Develop both the front and back-end in one language.</p></div></div><div id="w-node-_9c003888-73df-378e-051e-2da7c785f8a8-a4057bf2" class="is-row-l-h-c-32 is-margin-b-40"><p class="is-display is-l-hidden">cross-platform</p><div class="is-column is-max-w-350"><p class="is-h3 is-margin-b-16"><span class="is-hidden is-l-visible-inline">cross platform</span> capable</p><p class="is-sub-medium">Build across multiple operating systems and platforms.</p></div></div><div id="w-node-_9c003888-73df-378e-051e-2da7c785f8b2-a4057bf2" class="is-row-l-h-c-32 is-margin-b-40"><p class="is-display is-l-hidden">efficient</p><div class="is-column is-max-w-350"><p class="is-h3 is-margin-b-16"><span class="is-hidden is-l-visible-inline">efficient</span> and lean</p><p class="is-sub-medium">Streamline team structures and reduce duplication of work.</p></div></div><div id="w-node-_9c003888-73df-378e-051e-2da7c785f8bc-a4057bf2" class="is-row-l-h-c-32"><p class="is-display is-l-hidden">Smoother</p><div class="is-column is-max-w-350"><p class="is-h3 is-margin-b-16"><span class="is-hidden is-l-visible-inline">Smoother</span> safer, simpler</p><p class="is-sub-medium">We go beyond the brief to find and fix app performance issues.</p></div></div><div id="w-node-_1cc28742-adb7-21a6-783d-44d24e1800c0-a4057bf2" class="is-pad-t-24 is-align-center"><a href="#get-in-touch" class="btn-prm w-button">Get in touch</a></div></div></section><section id="our-services" class="is-section"><div class="hide w-embed w-script"><style> @media (min-width: 992px) { .our-services-dropdown-trigger .is-h3 { transition: color 0.3s ease; } .our-services-dropdown-trigger:hover .is-h3 { color: var(--colours-main--purple) !important; } } </style> <script> document.addEventListener('DOMContentLoaded', function() { document.querySelector('.our-services-dropdown-trigger').click(); }); </script></div><div class="is-container is-grid"><h2 id="w-node-_9df9e67f-d8e6-37b6-5f6b-41b2f14cc131-f14cc12e" class="is-h1 is-txt-align-center is-margin-b-80">our services</h2><div id="w-node-_9df9e67f-d8e6-37b6-5f6b-41b2f14cc133-f14cc12e" class="our-services-dropdown-holder"><div class="our-services-dropdown-wrapper"><div data-w-id="9df9e67f-d8e6-37b6-5f6b-41b2f14cc135" class="our-services-dropdown-trigger"><img src="https://cdn.prod.website-files.com/64d0b1ecf0fc228ea4057bb5/664f02630d323deab6b630da_arrows-right.svg" loading="lazy" alt="Right Arrow Purple" class="our-services-dropdown-arrow"/><p class="is-h3">Product Development and Growth</p></div><div class="our-services-dropdown"><div class="our-services-dropdown-grid"><div id="w-node-_9df9e67f-d8e6-37b6-5f6b-41b2f14cc13b-f14cc12e" class="is-column"><p class="is-sub-large is-margin-b-24">We help companies of all sizes develop innovative products that let them stayon top of the game.</p><div class="is-btn-wrap-c-mob"><a href="https://www.callstack.com/services/product-development-and-growth" class="btn-sec--dark w-button">Learn more</a></div></div><div id="w-node-_9df9e67f-d8e6-37b6-5f6b-41b2f14cc141-f14cc12e" class="our-services-dropdown-list-holder"><p id="w-node-_9df9e67f-d8e6-37b6-5f6b-41b2f14cc142-f14cc12e" class="is-txt-medium">Related products:</p><ul role="list" class="our-services-dropdown-list"><li class="is-text-link-dark"><a href="https://www.callstack.com/products/product-architecture" class="is-text-link-dark">Product Architecture</a></li><li class="is-text-link-dark"><a href="/product/mobile-app-development" class="is-text-link-dark">Mobile App Development</a></li><li class="is-text-link-dark"><a href="https://www.callstack.com/products/web-app-development" class="is-text-link-dark">Web App Development</a></li><li class="is-text-link-dark no-margin"><a href="https://www.callstack.com/products/integration-of-new-features-into-existing-apps" class="is-text-link-dark">Integration Of New Features Into Existing Apps</a></li></ul><ul role="list" class="our-services-dropdown-list"><li class="is-text-link-dark"><a href="https://www.callstack.com/products/integration-support-for-wearables-tv-consoles" class="is-text-link-dark">Integration Support For Wearables, TV, Consoles</a></li><li class="is-text-link-dark"><a href="https://www.callstack.com/products/app-testing-and-quality-assurance" class="is-text-link-dark">App Testing And Quality Assurance</a></li><li class="is-text-link-dark"><a href="https://www.callstack.com/products/app-maintenance" class="is-text-link-dark">App Maintenance</a></li><li class="is-text-link-dark"><a href="/product/full-stack-app-development-services" class="is-text-link-dark">Full Stack App Development</a></li></ul></div></div></div></div><div class="our-services-dropdown-wrapper"><div data-w-id="9df9e67f-d8e6-37b6-5f6b-41b2f14cc15c" class="our-services-dropdown-trigger"><img src="https://cdn.prod.website-files.com/64d0b1ecf0fc228ea4057bb5/664f02630d323deab6b630da_arrows-right.svg" loading="lazy" alt="Right Arrow Purple" class="our-services-dropdown-arrow"/><p class="is-h3">OPTIMIZATION OF PRODUCTS AND PROCESSES</p></div><div class="our-services-dropdown"><div class="our-services-dropdown-grid"><div id="w-node-_9df9e67f-d8e6-37b6-5f6b-41b2f14cc162-f14cc12e" class="is-column"><p class="is-sub-large is-margin-b-24">We provide everything you need to keep apps running smoothly and efficiently.</p><div class="is-btn-wrap-c-mob"><a href="https://www.callstack.com/services/optimization-of-products-and-processes" class="btn-sec--dark w-button">Learn more</a></div></div><div id="w-node-_9df9e67f-d8e6-37b6-5f6b-41b2f14cc168-f14cc12e" class="our-services-dropdown-list-holder"><p id="w-node-_9df9e67f-d8e6-37b6-5f6b-41b2f14cc169-f14cc12e" class="is-txt-medium">Related products:</p><ul id="w-node-_9df9e67f-d8e6-37b6-5f6b-41b2f14cc16b-f14cc12e" role="list" class="our-services-dropdown-list"><li class="is-text-link-dark"><a href="https://www.callstack.com/products/technical-debt-reduction-and-prevention" class="is-text-link-dark">Technical Debt Reduction And Prevention</a></li><li class="is-text-link-dark"><a href="https://www.callstack.com/product/app-performance-optimization" class="is-text-link-dark">App Performance Optimization</a></li><li class="is-text-link-dark"><a href="https://www.callstack.com/products/development-efficiency-boost" class="is-text-link-dark">Development Efficiency Boost</a></li><li class="is-text-link-dark no-margin"><a href="https://www.callstack.com/products/react-compiler-guided-implementation" class="is-text-link-dark">React Compiler Guided Implementation</a></li></ul></div></div></div></div><div class="our-services-dropdown-wrapper"><div data-w-id="9df9e67f-d8e6-37b6-5f6b-41b2f14cc176" class="our-services-dropdown-trigger"><img src="https://cdn.prod.website-files.com/64d0b1ecf0fc228ea4057bb5/664f02630d323deab6b630da_arrows-right.svg" loading="lazy" alt="Right Arrow Purple" class="our-services-dropdown-arrow"/><p class="is-h3">team UPSKILLING</p></div><div class="our-services-dropdown"><div class="our-services-dropdown-grid"><div id="w-node-_9df9e67f-d8e6-37b6-5f6b-41b2f14cc17c-f14cc12e" class="is-column"><p class="is-sub-large is-margin-b-24">We can equip your developers with the latest knowledge and tools.</p><div class="is-btn-wrap-c-mob"><a href="https://www.callstack.com/services/team-upskilling" class="btn-sec--dark w-button">Learn more</a></div></div><div id="w-node-_9df9e67f-d8e6-37b6-5f6b-41b2f14cc182-f14cc12e" class="our-services-dropdown-list-holder"><p id="w-node-_9df9e67f-d8e6-37b6-5f6b-41b2f14cc183-f14cc12e" class="is-txt-medium">Related products:</p><ul id="w-node-_9df9e67f-d8e6-37b6-5f6b-41b2f14cc185-f14cc12e" role="list" class="our-services-dropdown-list"><li class="is-text-link-dark"><a href="https://www.callstack.com/products/rapid-team-expansion" class="is-text-link-dark">Rapid Team Expansion</a></li><li class="is-text-link-dark"><a href="https://www.callstack.com/products/developer-training" class="is-text-link-dark">Developer Training</a></li><li class="is-text-link-dark"><a href="https://www.callstack.com/products/mentoring-program" class="is-text-link-dark">Mentoring Program</a></li><li class="is-text-link-dark no-margin"><a href="https://www.callstack.com/products/consulting" class="is-text-link-dark">Consulting</a></li></ul></div></div></div></div><div class="our-services-dropdown-wrapper"><div data-w-id="9df9e67f-d8e6-37b6-5f6b-41b2f14cc193" class="our-services-dropdown-trigger"><img src="https://cdn.prod.website-files.com/64d0b1ecf0fc228ea4057bb5/664f02630d323deab6b630da_arrows-right.svg" loading="lazy" alt="Right Arrow Purple" class="our-services-dropdown-arrow"/><p class="is-h3">TECH STACK UPGRADE</p></div><div class="our-services-dropdown"><div class="our-services-dropdown-grid"><div id="w-node-_9df9e67f-d8e6-37b6-5f6b-41b2f14cc199-f14cc12e" class="is-column"><p class="is-sub-large is-margin-b-24">Use up-to-date technologies to unlock new levels of performance, scalability, and efficiency.</p><div class="is-btn-wrap-c-mob"><a href="https://www.callstack.com/services/tech-stack-upgrade" class="btn-sec--dark w-button">Learn more</a></div></div><div id="w-node-_9df9e67f-d8e6-37b6-5f6b-41b2f14cc19f-f14cc12e" class="our-services-dropdown-list-holder"><p id="w-node-_9df9e67f-d8e6-37b6-5f6b-41b2f14cc1a0-f14cc12e" class="is-txt-medium">Related products:</p><ul id="w-node-_9df9e67f-d8e6-37b6-5f6b-41b2f14cc1a2-f14cc12e" role="list" class="our-services-dropdown-list"><li class="is-text-link-dark"><a href="https://www.callstack.com/products/architecture-redesign" class="is-text-link-dark">Architecture Redesign</a></li><li class="is-text-link-dark"><a href="https://www.callstack.com/products/adoption-of-a-cross-platform-approach" class="is-text-link-dark">Adoption Of A Cross-Platform Approach</a></li><li class="is-text-link-dark"><a href="/product/migration-to-react-native" class="is-text-link-dark">Migration To React Native</a></li><li class="is-text-link-dark no-margin"><a href="/product/the-bridge-module" class="is-text-link-dark">The Bridge Module</a></li></ul></div></div></div></div><div class="our-services-dropdown-wrapper"><div data-w-id="9df9e67f-d8e6-37b6-5f6b-41b2f14cc1ad" class="our-services-dropdown-trigger"><img src="https://cdn.prod.website-files.com/64d0b1ecf0fc228ea4057bb5/664f02630d323deab6b630da_arrows-right.svg" loading="lazy" alt="Right Arrow Purple" class="our-services-dropdown-arrow"/><p class="is-h3">BUSINESS TRANSFORMATION</p></div><div class="our-services-dropdown"><div class="our-services-dropdown-grid"><div id="w-node-_9df9e67f-d8e6-37b6-5f6b-41b2f14cc1b3-f14cc12e" class="is-column"><p class="is-sub-large is-margin-b-24">We specialize in helping businesses transform and thrive by leveraging innovative solutions.</p><div class="is-btn-wrap-c-mob"><a href="https://www.callstack.com/services/business-transformation" class="btn-sec--dark w-button">Learn more</a></div></div><div id="w-node-_9df9e67f-d8e6-37b6-5f6b-41b2f14cc1b9-f14cc12e" class="our-services-dropdown-list-holder"><p id="w-node-_9df9e67f-d8e6-37b6-5f6b-41b2f14cc1ba-f14cc12e" class="is-txt-medium">Related products:</p><ul role="list" class="our-services-dropdown-list"><li class="is-text-link-dark"><a href="https://www.callstack.com/products/learning-and-development-strategies" class="is-text-link-dark">Learning And Development Strategies</a></li><li class="is-text-link-dark no-margin"><a href="https://www.callstack.com/products/workstreams-optimization" class="is-text-link-dark">Workstreams’ Optimization</a></li></ul><ul role="list" class="our-services-dropdown-list"><li class="is-text-link-dark"><a href="https://www.callstack.com/products/work-efficiency" class="is-text-link-dark">Work Efficiency</a></li><li class="is-text-link-dark"><a href="https://www.callstack.com/products/tech-scalability" class="is-text-link-dark">Tech Scalability</a></li><li class="is-text-link-dark"><a href="https://www.callstack.com/products/product-shipment-acceleration" class="is-text-link-dark">Product Shipment Acceleration</a></li></ul></div></div></div></div></div></div></section><section class="is-section overflow-hidden"><div class="is-container is-grid"><div id="w-node-d811186c-d7ef-f73f-5f3c-2f400096a802-0096a800" class="column center"><h2 class="is-h1">Case studies</h2></div><div id="w-node-a1cd54af-638f-2597-bdc8-a17b5b81b73c-5b81b73c" class="case-studies-swiper-wrapper"><div id="case-studies-swiper" class="case-studies-wrapper w-dyn-list"><div role="list" class="swiper-wrapper w-dyn-items"><div role="listitem" class="swiper-slide case-studies-slide cursor-pointer w-dyn-item"><a href="/case-studies/thriva" class="case-studies-wrapper-card drop-shadow w-inline-block"><div class="case-studies-quote-wrapper-rebrand"><div class="is-sub-medium">“Callstack played an essential role in helping us release our mobile app to the market. They helped us set up and optimise our mobile ecosystem.”</div><div class="column flex-right"><div class="is-txt-small">Donovan Isherwood - Engineering Manager</div></div></div><div class="card-vertical-divider is-l-hidden"></div><div class="column full-height case-study-carousel-name-column"><div class="is-txt-light is-txt-allcaps">Thriva</div><h3 class="is-h3 is-margin-b-auto">Accelerating Thriva’s Health App Time-to-Market and Development</h3><div class="is-txt-medium is-fake-link-underlined-white">More</div></div><div class="case-studies-card-logo drop-shadow case-studies-carousel-logo-rebrand"><img alt="Thriva" loading="lazy" src="https://cdn.prod.website-files.com/64d4ce10600bd67e51c42838/650d5ca6a05ab35bc19faf12_thriva.png" class="card-logo-image"/></div></a></div><div role="listitem" class="swiper-slide case-studies-slide cursor-pointer w-dyn-item"><a href="/case-studies/coinmine" class="case-studies-wrapper-card drop-shadow w-inline-block"><div class="case-studies-quote-wrapper-rebrand"><div class="is-sub-medium">“Callstack is one of the best software teams I've ever worked with. 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I definitely recommend the Callstack team!”</div><div class="column flex-right"><div class="is-txt-small">Glen Moriarty - Founder and CEO</div></div></div><div class="card-vertical-divider is-l-hidden"></div><div class="column full-height case-study-carousel-name-column"><div class="is-txt-light is-txt-allcaps">7 Cups</div><h3 class="is-h3 is-margin-b-auto">7 Cups App Upgrade Generates a 130% Increase in the Number of Users</h3><div class="is-txt-medium is-fake-link-underlined-white">More</div></div><div class="case-studies-card-logo drop-shadow case-studies-carousel-logo-rebrand"><img alt="7 Cups" loading="lazy" src="https://cdn.prod.website-files.com/64d4ce10600bd67e51c42838/6509cbd380a3f951a04368fe_7cups.png" class="card-logo-image"/></div></a></div></div></div><div class="swiper-button-wrapper"><a id="case-study-prev" data-w-id="a1cd54af-638f-2597-bdc8-a17b5b81b751" href="#" class="arrow-big swiper-button w-inline-block"><div data-w-id="a1cd54af-638f-2597-bdc8-a17b5b81b752" 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