expo-dev-client

SKILL.md

Build custom Expo development clients for testing native code on physical devices via EAS Build or locally.

Only needed when using custom native modules, Apple targets (widgets, app clips), or third-party native code not in Expo Go; try Expo Go first with npx expo start

Supports cloud builds with automatic TestFlight submission or local builds on your machine, outputting .ipa (iOS) or .apk/.aab (Android) files

Requires eas.json configuration with a development profile that sets developmentClient: true and autoIncrement: true

Once installed, the dev client launcher UI connects to your local Metro bundler via URL or QR code for live development and native code testing

Use EAS Build to create development clients for testing native code changes on physical devices. Use this for creating custom Expo Go clients for testing branches of your app.

Free locally; cloud builds are paid. expo-dev-client itself is open source and building locally is free. Building or distributing via EAS Build/TestFlight uses your EAS plan's build minutes and needs a paid Apple Developer account for device/TestFlight distribution. See https://expo.dev/pricing.

Important: When Development Clients Are Needed

Development clients are the recommended setup for any real or production app. Expo Go is a playground for learning and quick experiments with the native libraries it bundles; most apps outgrow it and move to a development client. See Expo Go vs. development builds for the full reasoning.

You need a dev client ONLY when using:

Local Expo modules (custom native code)

Apple targets (widgets, app clips, extensions)

Third-party native modules not in Expo Go

Config plugins, or testing remote push notifications and App/Universal Links

EAS Configuration

Ensure eas.json has a development profile: