> ## Documentation Index
> Fetch the complete documentation index at: https://mintlify.com/expo/expo/llms.txt
> Use this file to discover all available pages before exploring further.

# Overview

> Learn about Expo CLI, the command-line tool for developing Expo applications.

Expo CLI is the official command-line interface for Expo projects. It provides a comprehensive set of tools for developing, building, and deploying React Native applications with Expo.

## What is Expo CLI?

Expo CLI is distributed as the `@expo/cli` npm package and serves as the primary interface for:

* Starting development servers with Metro bundler
* Building and running native applications locally
* Generating native iOS and Android projects
* Managing dependencies compatible with your Expo SDK version
* Exporting production-ready bundles
* Authenticating with your Expo account

The CLI is designed with a lean, intentional public interface where all commands and arguments are carefully considered.

## Main Features

### Development Server

The CLI provides a powerful development server with Metro bundler integration that supports:

* Multi-platform bundling (iOS, Android, and Web)
* Hot Module Replacement (HMR)
* Fast Refresh for instant updates
* Chrome DevTools Protocol for debugging
* TypeScript support with automatic type generation
* Server-side rendering and API routes

### Native Development

Build and run your app on iOS simulators, Android emulators, and physical devices:

* Automatic device detection and selection
* Xcode and Gradle build integration
* Code signing management for iOS
* Variant and configuration support

### Project Management

* Generate native projects with `expo prebuild`
* Install compatible dependencies with `expo install`
* View resolved configuration with `expo config`
* Customize Metro bundler and native projects

## Common Workflows

### Starting Development

```bash theme={null}
npx expo start
```

Opens an interactive terminal UI where you can:

* Press `i` to open iOS simulator
* Press `a` to open Android emulator
* Press `w` to open in web browser
* Scan QR code with Expo Go or development build

### Building Locally

```bash theme={null}
# Build and run on iOS
npx expo run:ios

# Build and run on Android
npx expo run:android
```

These commands compile your native code and launch the app on a simulator/emulator or physical device.

### Generating Native Projects

```bash theme={null}
npx expo prebuild
```

Creates `ios/` and `android/` directories with native code that you can open in Xcode or Android Studio.

### Installing Dependencies

```bash theme={null}
npx expo install react-native-maps
```

Installs packages with versions compatible with your Expo SDK version.

### Exporting for Production

```bash theme={null}
npx expo export
```

Creates optimized production bundles for deployment, including:

* Minified JavaScript
* Compressed assets
* Platform-specific bundles
* Static HTML for web

## Requirements

* Node.js 20.19.4 or newer (LTS version recommended)
* npm, yarn, pnpm, or bun package manager
* For iOS development: macOS with Xcode (not supported on Windows)
* For Android development: Android Studio or Android SDK

## Getting Help

Run any command with the `--help` flag to see detailed usage information:

```bash theme={null}
npx expo start --help
npx expo run:ios --help
npx expo prebuild --help
```

## Environment Variables

Expo CLI supports various environment variables for customization:

* `EXPO_DEBUG=1` - Enable debug logging
* `EXPO_OFFLINE=1` - Skip network requests
* `CI=1` - Run in non-interactive CI mode
* `EXPO_NO_TELEMETRY=1` - Disable analytics

See the [Environment Variables](/cli/configuration/environment-variables) page for a complete list.