Testing
Detox and Appium are the two dominant mobile E2E testing frameworks, but they take fundamentally different approaches. Detox is a gray-box framework purpose-built for React Native — fast and reliable but React Native only. Appium is a black-box framework that works with any mobile app on any platform
Testing
Detox is a gray-box end-to-end testing framework for React Native that synchronizes test execution with your app's internal state — eliminating the sleep() calls and timing hacks that make black-box tests brittle. This guide covers the architecture that makes Detox work and walks you through
React Native
A hands-on guide to Detox E2E testing in React Native, covering project setup, device and element APIs, synchronization with async operations, and running Detox in CI environments like GitHub Actions. Detox is the industry-standard end-to-end testing framework for React Native. Unlike Jest + RNTL which runs in
Testing
Running Detox tests in CI requires matching simulator/emulator availability to your runner OS, caching dependencies, and handling the slow parts (app builds, simulator boot) efficiently. This guide covers complete CI configurations for GitHub Actions and GitLab CI for both iOS and Android. Key Takeaways * iOS requires macOS runners — this
Testing
Flaky Detox tests almost always come from one of three sources: broken synchronization (the app isn't idle when Detox thinks it is), poor test isolation (state from one test bleeds into the next), or incorrect element selectors (the testID you're targeting doesn't exist in
React Native
A comprehensive walkthrough of React Native Testing Library with Jest, covering renderHook for custom hooks, userEvent for realistic interactions, the full query API, async utilities, and accessibility-first testing patterns. React Native Testing Library (RNTL) has matured into the standard way to test React Native components and hooks. Paired with
React Native
Snapshot testing in React Native can catch unintended UI regressions, but done wrong it becomes a rubber-stamp exercise. This post covers when snapshots add value, how to write focused inline snapshots, and patterns that keep your snapshot suite meaningful over time. Snapshot testing is one of the most misused
React Native
Testing navigation in React Native requires mocking React Navigation's hooks and prop injection, verifying that screens navigate correctly in response to user actions, and testing deep links and complex stack flows. This post covers the full range of navigation testing patterns. Navigation is one of the trickiest parts
React Native
A deep dive into mocking native modules in React Native Jest tests, covering inline jest.mock patterns, the mocks directory, NativeEventEmitter simulation, and writing robust manual mocks for complex native APIs like Camera, Location, and Bluetooth. Native modules are the bridge between JavaScript and platform APIs like the camera, GPS,
Expo
Expo adds a layer of abstraction over React Native that requires specific testing strategies. The jest-expo preset handles most of the configuration complexity, but mocking expo-* modules, testing Expo Router's file-based navigation, and connecting Detox to the bare workflow each have their own patterns. This guide
React Native
Testing React Native applications introduces a unique set of challenges that don't exist in web testing.
Detox
End-to-end testing of mobile apps has historically been plagued by flakiness. Tests that pass locally fail in CI.