Expo SDK

Core Functionality

Expo SDK provides a comprehensive toolkit for building React Native applications with file-based routing through Expo Router. This skill covers navigation patterns, media handling, data persistence, authentication, device hardware integration, and third-party service integration.

When to Use

This skill should be used when users need to work with Expo SDK and Expo Router for building React Native applications. It provides comprehensive guidance on navigation patterns, media handling (camera, image, video, audio), data storage (SQLite, filesystem, SecureStore), authentication, device features (location, notifications, biometrics), and third-party integrations (Stripe, linking, sharing).

Module Overview

Navigation Module

• Functionality: Comprehensive file-based routing system with support for stack, tabs, drawer, and modal navigators. Includes dynamic routes, protected routes, redirects, and deep linking capabilities.
• Key APIs: useRouter, Link, Stack, Tabs, Drawer, Modal, Redirect, useLocalSearchParams, router.navigate, router.push, router.back, router.replace, router.setParams
• Detailed documentation: references/navigation.mdx, references/stack.mdx, references/tabs.mdx, references/drawer.mdx, references/modals.mdx, references/redirects.mdx

Authentication Module

• Functionality: Client-side authentication patterns using React Context, protected routes, session management, and SecureStore integration for secure credential storage.
• Key APIs: Stack.Protected, useSession, SessionProvider, SecureStore.setItemAsync, SecureStore.getItemAsync, Redirect
• Detailed documentation: references/authentication.mdx, references/authentication-rewrites.mdx, references/protected.mdx

Media Module

• Functionality: Camera access and preview, image loading with caching, image manipulation, media library access, video playback, audio recording and playback, and Live Photo support.
• Key APIs: CameraView, useCameraPermissions, Image, useVideoPlayer, VideoView, useAudioPlayer, useAudioRecorder, ImageManipulator, MediaLibrary.getAssetsAsync, launchImageLibraryAsync
• Detailed documentation: references/camera.mdx, references/image.mdx, references/video.mdx, references/audio.mdx, references/imagepicker.mdx, references/imagemanipulator.mdx, references/media-library.mdx

Storage Module

• Functionality: SQLite database operations with async/await patterns, filesystem access for file operations, and encrypted key-value storage for sensitive data.
• Key APIs: SQLite.openDatabaseAsync, execAsync, runAsync, getFirstAsync, getAllAsync, prepareAsync, withTransactionAsync, FileSystem.downloadFileAsync, File, Directory, SecureStore.setItemAsync, SecureStore.getItemAsync
• Detailed documentation: references/sqlite.mdx, references/filesystem.mdx, references/securestore.mdx

Device Module

• Functionality: Geolocation tracking with background support, push and local notifications, biometric authentication (Face ID, Touch ID, fingerprint), and background task management.
• Key APIs: Location.requestForegroundPermissionsAsync, Location.getCurrentPositionAsync, Location.watchPositionAsync, Notifications.scheduleNotificationAsync, Notifications.addNotificationReceivedListener, LocalAuthentication.authenticateAsync
• Detailed documentation: references/location.mdx, references/notifications.mdx, references/local-authentication.mdx, references/task-manager.mdx

Integration Module

• Functionality: Deep linking and universal links, file sharing between apps, Stripe payment integration, Apple Handoff for cross-device continuity, clipboard access, and native intent handling.
• Key APIs: Linking.openURL, Linking.createURL, Sharing.shareAsync, initStripe, PaymentSheet, Clipboard.setStringAsync, Clipboard.getStringAsync
• Detailed documentation: references/linking.mdx, references/sharing.mdx, references/stripe.mdx, references/apple-handoff.mdx, references/clipboard.mdx

Workflow

Navigation and Routing

1. Define file-based routes using app/ directory structure with special notation (square brackets for dynamic routes, parentheses for route groups, underscore for layouts)
2. Use useRouter() for imperative navigation (router.push(), router.back(), router.replace())
3. Use <Link> component for declarative navigation
4. Implement layouts with _layout.tsx files to configure navigators (Stack, Tabs, Drawer)
5. Reference detailed navigation patterns in references/navigation.mdx and references/notation.mdx

Authentication Implementation

1. Create authentication context with useSession hook for session state management
2. Use Stack.Protected or Tabs.Protected for protected route groups
3. Store credentials securely using SecureStore API
4. Implement redirects for unauthenticated users using <Redirect> component
5. Reference complete authentication guides in references/authentication.mdx

Media Handling

1. Request permissions using useCameraPermissions or MediaLibrary.usePermissions
2. Use <CameraView> component for camera functionality
3. Load images with <Image> component for optimized caching and performance
4. Implement video playback with useVideoPlayer hook and <VideoView> component
5. Reference media APIs in references/camera.mdx, references/image.mdx, references/video.mdx

Data Persistence

1. For structured data: Use SQLite.openDatabaseAsync() with async/await for database operations
2. For secure credentials: Use SecureStore.setItemAsync() and getItemAsync()
3. For file operations: Use FileSystem API for downloads, uploads, and directory management
4. Reference storage solutions in references/sqlite.mdx, references/securestore.mdx, references/filesystem.mdx

Device Features

1. Location: Request foreground/background permissions, then use Location.getCurrentPositionAsync() or Location.watchPositionAsync()
2. Notifications: Configure with Notifications.setNotificationHandler(), then schedule with Notifications.scheduleNotificationAsync()
3. Biometrics: Use LocalAuthentication.authenticateAsync() for fingerprint/Face ID authentication
4. Reference device-specific guides in references/location.mdx, references/notifications.mdx, references/local-authentication.mdx

Third-Party Integration

1. Deep linking: Configure linking in app.config.js, use Linking.openURL() or <Link> component
2. Stripe payments: Initialize with initStripe(), use PaymentSheet for payment flow
3. Sharing: Use Sharing.shareAsync() to share files and content
4. Reference integration guides in references/stripe.mdx, references/linking.mdx, references/sharing.mdx

Common Patterns

Dynamic Routes

Use square brackets in file names (e.g., [id].tsx) and access parameters with useLocalSearchParams() hook.

Protected Routes

Wrap authenticated screens with <Stack.Protected> or use client-side redirects based on session context.

Modal Presentation

Create files inside ../modal/ directory or use <Modal> from React Native for custom presentations.

Background Tasks

Define tasks with TaskManager.defineTask() and configure location updates or notifications in background.

Resource References

Navigation & Routing

• File-based routing basics: references/navigation.mdx
• Route notation reference: references/notation.mdx
• Stack navigator: references/stack.mdx
• Tabs navigator: references/tabs.mdx
• Modals: references/modals.mdx
• Redirects: references/redirects.mdx

Authentication

• Protected routes (SDK 53+): references/authentication.mdx
• Authentication patterns (SDK 52): references/authentication-rewrites.mdx
• Protected components: references/protected.mdx

Media Handling

• Camera: references/camera.mdx
• Image loading: references/image.mdx
• Video playback: references/video.mdx
• Audio: references/audio.mdx
• Image picker: references/imagepicker.mdx
• Media library: references/media-library.mdx

Storage & Data

• SQLite database: references/sqlite.mdx
• File system: references/filesystem.mdx
• Secure storage: references/securestore.mdx

Device Features

• Location services: references/location.mdx
• Notifications: references/notifications.mdx
• Biometric auth: references/local-authentication.mdx
• Background tasks: references/task-manager.mdx

Integration

• Stripe payments: references/stripe.mdx
• Deep linking: references/linking.mdx
• Sharing: references/sharing.mdx
• Apple Handoff: references/apple-handoff.mdx
• Clipboard: references/clipboard.mdx

For complete API specifications, advanced configurations, and platform-specific considerations, refer to the detailed documentation in the references/ directory.