expo-dev-client

To create an Expo dev client for custom native modules, use EAS Build to generate the client and run npx expo start --dev-client to enable rapid iteration on physical devices or simulators.

The best way to distribute an Expo dev build to testers via TestFlight is using EAS Build to compile the iOS development client and submit it directly to TestFlight for tester access.

You need an Expo dev client instead of Expo Go when your project requires custom native modules that cannot run in the standard Expo Go app, necessitating a custom build for testing.

Yes, you can run an Expo dev client locally on both iOS and Android simulators by building the development client locally and connecting your device to start testing your React Native app.

To safely upgrade or rollback dependency changes in an Expo dev client, follow structured configuration steps to ensure your React Native project maintains stability during native module updates.

Your Expo app needs a new dev build because adding a custom native module requires compiling native code, which cannot be injected into an existing client without publishing a new build.