dev-client

Only create development clients when your app requires custom native code. Most apps work fine in Expo Go.

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

Try Expo Go first with npx expo start. If everything works, you don't need a dev client.

Ensure eas.json has a development profile:

```json

{

"cli": {

"version": ">= 16.0.1",

"appVersionSource": "remote"

},

"build": {

"production": {

"autoIncrement": true

},

"development": {

"autoIncrement": true,

"developmentClient": true

}

},

"submit": {

"production": {},

"development": {}

}

}

```

Key settings:

• developmentClient: true - Bundles expo-dev-client for development builds
• autoIncrement: true - Automatically increments build numbers
• appVersionSource: "remote" - Uses EAS as the source of truth for version numbers

Build iOS dev client and submit to TestFlight in one command:

```bash

eas build -p ios --profile development --submit

```

This will:

1. Build the development client in the cloud
2. Automatically submit to App Store Connect
3. Send you an email when the build is ready in TestFlight

After receiving the TestFlight email:

1. Download the build from TestFlight on your device
2. Launch the app to see the expo-dev-client UI
3. Connect to your local Metro bundler or scan a QR code

Build a development client on your machine:

```bash

# iOS (requires Xcode)

eas build -p ios --profile development --local

# Android

eas build -p android --profile development --local

```

Local builds output:

• iOS: .ipa file
• Android: .apk or .aab file

Install iOS build on simulator:

```bash

# Find the .app in the .tar.gz output

tar -xzf build-*.tar.gz

xcrun simctl install booted ./path/to/App.app

```

Install iOS build on device (requires signing):

```bash

# Use Xcode Devices window or ideviceinstaller

ideviceinstaller -i build.ipa

```

Install Android build:

```bash

adb install build.apk

```

```bash

# iOS only

eas build -p ios --profile development

# Android only

eas build -p android --profile development

# Both platforms

eas build --profile development

```

```bash

# List recent builds

eas build:list

# View build details

eas build:view

```

Once installed, the dev client provides:

• Development server connection - Enter your Metro bundler URL or scan QR
• Build information - View native build details
• Launcher UI - Switch between development servers

Connect to local development:

```bash

# Start Metro bundler

npx expo start --dev-client

# Scan QR code with dev client or enter URL manually

```

Build fails with signing errors:

```bash

eas credentials

```

Clear build cache:

```bash

eas build -p ios --profile development --clear-cache

```

Check EAS CLI version:

```bash

eas --version

eas update

```