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iOS, Android, React Native, and Flutter, tested on real devices when it matters

Mobile testing services built for real devices, not just simulators

Mobile testing often gets reduced to tapping through the app on a simulator, checking that buttons do what they're supposed to. That's necessary, but it's not enough. Mobile apps fail in production for reasons that have nothing to do with button behavior: device fragmentation, permission handling, offline behavior, and battery conditions a simulator can't fully replicate.

What mobile testing covers beyond tapping through the app

Functional testing on a simulator is necessary. It is not sufficient.

Device compatibility

Screen sizes, notched displays, foldables, and the manufacturer customizations that change how a layout actually renders.

Installation and upgrade paths

Fresh installs, version upgrades, data preservation, and the downgrade scenarios most teams never think to check.

Permission handling

Denied permissions, runtime revocation, and whether the app degrades gracefully or just breaks.

Offline and poor network behavior

What happens when a network drops mid-operation, and whether the app's data stays consistent when it comes back.

Battery and memory conditions

Low battery, battery saver mode, and the memory leaks that only surface after extended real-world use.

Background and foreground transitions

Whether state actually survives a backgrounding, and whether an in-progress operation resumes or just quietly fails.

iOS and Android are different platforms

A team that tests only on one and assumes the other will be fine routinely ships platform-specific bugs a dedicated pass would have caught.

Android

Fragmentation across thousands of device configurations and manufacturers. Custom OS layers like One UI and MIUI handle permissions, notifications, and background processing differently from stock Android. We prioritize the device and OS combinations your actual analytics show people using. Automated through Espresso natively or Appium cross-platform.

iOS

More consistent across devices since Apple controls the hardware, but App Store review requirements are stricter. Privacy policies, permission descriptions, and App Tracking Transparency need testing against Apple’s policies with every major iOS version. Automated through XCUITest natively or Detox for React Native.

  • Testing only on the latest iOS or Android version, ignoring the users who haven't updated.
  • Testing solely on the developer's own device, missing device-specific issues entirely.

Testing cross-platform apps

React Native and Flutter each need their own testing approach, plus coverage of the integration points shared across both: deep links, push notifications, payment flows, and share sheets.

React Native

The shared JavaScript layer handles business logic, tested with Jest, but platform-specific bridges handle camera access, push notifications, deep linking, and native UI components. Those get tested separately: Detox on iOS, Appium on Android, since bridge implementations differ enough to need it.

Flutter

Flutter renders its own UI with its own graphics engine, which makes rendering more consistent across platforms than React Native, but it also means Flutter apps skip native UI components entirely, which raises its own accessibility testing considerations.

Real devices vs. emulators

Emulators are faster to set up and cover more configurations, but they can’t fully replicate real device behavior for everything.

When an emulator is enough

Most functional testing, UI layout verification, network throttling, basic performance profiling, and compatibility checks across standard screen sizes.

When a real device is required

Biometric authentication, camera and microphone behavior, Bluetooth and NFC, gyroscope and accelerometer response, real battery and thermal behavior, and push notifications on specific device and OS combinations.

For the middle ground, BrowserStack’s real device cloud gives access to hundreds of physical devices without a lab to maintain, with reserved physical devices on hand for the scenarios cloud testing still can’t cover.

Frequently asked questions

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