# Why Android Emulators Fall Short for Testing React Native Apps - Canonical: https://33rdsquare.com/why-android-emulators-fall-short-for-testing-react-native-apps/ - Published: 2024-03-06 - Author: Brian Lucas - Categories: [App & Browser Testing Automation](https://33rdsquare.com/category/browser/browser-testing/) --- React Native has exploded in popularity as a framework for building cross-platform mobile apps with JavaScript. By allowing developers to reuse code across iOS, Android and web apps, React Native can greatly accelerate development and reduce overall engineering effort. However, testing and quality assurance remains a crucial step before releasing any mobile app into the wild. And this is where many developers run into issues when relying solely on Android and iOS emulators to validate their React Native apps. In this guide, we‘ll cover the key disadvantages of emulators for testing React Natove, and why real devices hosted in the cloud are a far better solution for complete and reliable app testing. ## The Promises and Perils of React Native React Native enables you to build mobile apps with JavaScript that run natively on both iOS and Android. Instead of managing separate Objective-C and Java/Kotlin codebases, you can write once and deploy everywhere. React Native uses the same fundamental UI building blocks as regular iOS and Android apps. But instead of using platform-specific UI widgets, you construct these native-like UI components with JavaScript using React. This means you get the fast performance of native code without the development overhead of platform-specific languages. No wonder React Native adoption has grown rapidly in recent years. However, the biggest challenge with React Native comes when you need to test and quality-assure your mobile apps before release. Since React Native allows cross-platform code reuse, this requires testing against both iOS and Android environments. And here is where Android and iOS emulators fall painfully short. ## Why Android and iOS Emulators Fail for Comprehensive Testing Developers often rely on emulators like the Android Studio emulator during day-to-day React Native development. Emulators allow prototyping apps right on your local machine without needing physical devices handy. However, emulators only provide limited utility when you need to comprehensively test React Native apps before release: **Performance Does Not Match Real Devices** The Android emulator runs on your development machine’s CPU, not a mobile device ARM chipset. This means performance will never realistically match an actual smartphone or tablet. Complex UIs, animations and gestures that run smoothly on an emulator may still get janky on real users’ devices. So you can’t rely on emulator testing alone if you want confidence in your app‘s production-readiness. **Native Hardware Integration Cannot Be Tested** React Native allows JavaScript access to many native hardware APIs like GPS, camera and Bluetooth. Emulators cannot accurately replicate all these device interactions. So hardware-related bugs will always slip through if you test React Native apps only with emulators. This leads to broken features and crashes when real users access these device APIs. **App Usage Cannot Scale** Emulators reside on your local development machine, which has limited hardware capacity. You can’t simulate thousands of concurrent users running your app on different devices like in the real world. So performance, stability and infrastructure testing with scale is impossible with emulators alone. Without testing scale, you risk app crashes as soon as user traffic spikes after launch. **Fragmented Android Ecosystem Not Covered** There are over 24,000 distinct Android device types and OS versions active today. Manually maintaining a representative set emulators for all these configurations is infeasible. So critical Android-specific bugs will invariably pass through emulator testing and only surface post app-launch. This results in broken functionality and crashes for significant segments of Android users. Clearly emulators alone cannot deliver the breadth, depth and reliability of testing required for React Native apps before you release to real production users across iOS and Android. ## Why Real Devices in the Cloud is the Superior Testing Approach Real smartphones and tablets provide the only way to fully validate React Native mobile apps at enterprise-grade fidelity before launch: **Test Performance Under Real-World Conditions** Real mobile devices demonstrate actual app performance metrics you can expect in the wild across locations, connectivity conditions and hardware. No approximations here – just the real McCoy. Testing with real devices identifies performance bottlenecks like UI jank, laggy interactions, slow load times etc. far more accurately upfront, allowing developers to fix these efficiently before users ever find them. **Interact With Real Native Hardware and Software** Actual smartphones and tablets enable you to test all native device hardware capabilities supported by React Native – camera, GPS, notifications, fingerprint auth etc. Real devices also include the genuine Android and iOS software with all their underlying processes, services and UI quirks. This finds hardware and OS-specific bugs utterly missed by emulators. **Scale to Any Number of Users** With a vast cloud of thousands of real devices, you can simulate tremendous user loads across device types to stress-test performance, stability and infrastructure scalability. Catch crashes, regressions, bottlenecks and infrastructure limitations effectively before launch with large-scale real device testing. Confidently scale your React Native apps to any expected user volumes right out the gates. **Test Across All Android Device Fragmentation** The cloud grants you instant on-demand access to thousands of real Android device types – including various generations of Samsung, Sony, Motorola, Huawei, Xiaomi and other phones & tablets. This allows exhaustive testing across Android OS versions, screen sizes and hardware configs to catch Android-specific issues no single emulator setup could ever replicate. In summary, real devices in the cloud enable true-to-life testing of React Native mobile apps across the entire breadth of Android and iOS environments – delivering the confidence to release quality digital experiences to real-world consumers. ## Access Thousands of Real Devices On-Demand with BrowserStack While procuring and maintaining a large-scale real device lab in-house is extremely complex and expensive, cloud services make this a whole lot easier by offering on-demand access to shared device infrastructure. **BrowserStack in particular is a popular cloud-based testing platform for validating websites and mobile applications across thousands of unique real desktop browsers, smart devices and operating system environments.** Some key capabilities include: - Instant access to 2000+ unique real mobile devices running Android and iOS. - Coverage across all Android fragmentation – OS versions, SKUs, chipsets etc. - Supports both manual and automated testing of mobile apps. - Debugging tools for screenshots, video, logs and device vitals. - Real-world network simulations - Testing device hardware capabilities - CI/CD integrations BrowserStack streamlines React Native testing by providing instantaneous access to the entirety of Android and iOS environments from desktop browsers and CI/CD pipelines – no physical devices required. The platform scales seamlessly as your test needs grow, maintaining fresh device inventory as new mobile hardware, OS versions and device profiles continually launch. **Try BrowserStack for free to test React Native apps across 2000+ real Android and iOS devices today.** Discover why leading enterprises rely on BrowserStack for reliable mobile CI/CD and pre-production testing. --- Source: [Why Android Emulators Fall Short for Testing React Native Apps](https://33rdsquare.com/why-android-emulators-fall-short-for-testing-react-native-apps/)