building-ui

# Expo UI Guidelines

## References

Consult these resources as needed:

- ./references/route-structure.md -- Route file conventions, dynamic routes, query parameters, groups, and folder organization
- ./references/tabs.md -- Native tab bar with NativeTabs, migration from JS tabs, iOS 26 features
- ./references/icons.md -- SF Symbols with expo-symbols, common icon names, animations, and weights
- ./references/controls.md -- Native iOS controls: Switch, Slider, SegmentedControl, DateTimePicker, Picker
- ./references/visual-effects.md -- Blur effects with expo-blur and liquid glass with expo-glass-effect
- ./references/animations.md -- Reanimated animations: entering, exiting, layout, scroll-driven, and gestures
- ./references/search.md -- Search bar integration with headers, useSearch hook, and filtering patterns
- ./references/gradients.md -- CSS gradients using experimental_backgroundImage (New Architecture only)
- ./references/media.md -- Media handling for Expo Router including camera, audio, video, and file saving
- ./references/storage.md -- Data storage patterns including SQLite, AsyncStorage, and SecureStore
- ./references/webgpu-three.md -- 3D graphics, games, and GPU-powered visualizations with WebGPU and Three.js

## Running the App

**CRITICAL: Always try Expo Go first before creating custom builds.**

Most Expo apps work in Expo Go without any custom native code. Before running `npx expo run:ios` or `npx expo run:android`:

1. **Start with Expo Go**: Run `npx expo start` and scan the QR code with Expo Go
2. **Check if features work**: Test your app thoroughly in Expo Go
3. **Only create custom builds when required** - see below

### When Custom Builds Are Required

You need `npx expo run:ios/android` or `eas build` ONLY when using:

- **Local Expo modules** (custom native code in `modules/`)
- **Apple targets** (widgets, app clips, extensions via `@bacons/apple-targets`)
- **Third-party native modules** not included in Expo Go
- **Custom native configura