ranbot-ai/skills/expo-ui

Expo UI (@expo/ui)

When to Use

Use this skill when you need build native UI with the @expo/ui package: real SwiftUI on iOS and Jetpack Compose on Android rendered from React in an Expo or React Native app. Covers universal cross-platform components (Host, Column, Row, Button, Text, List, and more imported from @expo/ui), drop-in replacements...

@expo/ui renders real native UI from React: SwiftUI on iOS, Jetpack Compose on Android. Start with its universal components (one tree for iOS, Android, and web) and drop to platform-specific SwiftUI/Jetpack Compose only when the universal layer falls short. It also ships drop-in replacements for migrating off RN community UI libraries.

These instructions track the latest Expo SDK. The universal layer requires SDK 56+. Drop-in replacements and the platform-specific layers also exist on SDK 55. For component details on a specific SDK, refer to the Expo UI docs for that version.

Installation

npx expo install @expo/ui

On SDK 56, @expo/ui works in Expo Go, so npx expo start runs it directly — no custom build required. On older SDKs, build a dev client first (npx expo run:ios / npx expo run:android).

Every @expo/ui tree — universal or platform-specific — must be wrapped in Host.

Choosing an approach (read this first)

Work down this list and stop at the first layer that meets the need:

1. Universal components — start here. Import from the @expo/ui root. One component tree runs unmodified on iOS, Android, and web from a single source (Compose on Android, SwiftUI on iOS, react-native-web/react-dom on web). No platform file splits. → ./references/universal.md

2. Platform-specific (SwiftUI / Jetpack Compose). Import from @expo/ui/swift-ui or @expo/ui/jetpack-compose. Use only when the universal layer is missing a component or modifier you need, or when you need platform-specific behavior or optimization. Downside: you write two trees and split them into .ios.tsx / .android.tsx files (or branch on Platform.OS) — more code to maintain.

   @expo/ui/swift-ui is iOS-only. @expo/ui/jetpack-compose is Android-only. Importing either in a file that runs on the other platform will crash at runtime with "Unable to get view config" errors. Isolate platform-specific trees in .ios.tsx / .android.tsx files placed in components/ (never inside app/ — Expo Router does not support platform extensions for route files), or guard with Platform.OS in a regular route file. Host must always be imported from @expo/ui (the universal package root), not from the platform-specific sub-packages. → ./references/swift-ui.md and ./references/jetpack-compose.md

Already using an RN community UI library? @expo/ui also ships drop-in replacements — API-compatible swaps for popular libraries (@gorhom/bottom-sheet, @react-native-community/datetimepicker, and more), imported from @expo/ui/community/<name>. This is a migration side-path for replacing an existing dependency, not a step in the universal-vs-platform decision above. → ./references/drop-in-replacements.md

References

Consult these resources as needed:

references/
  universal.md             Universal @expo/ui components and when to use them (SDK 56+)
  drop-in-replacements.md  API-compatible replacements for RN community UI libraries
  swift-ui.md              Platform-specific iOS UI: @expo/ui/swift-ui components, modifiers, RNHostView, useNativeState
  jetpack-compose.md       Platform-specific Android UI: @expo/ui/jetpack-compose components, modifiers, LazyColumn caveat, icons, useNativeState

Limitations

• Use this skill only when the task clearly matches its upstream product or API scope.
• Verify commands, API behavior, pricing, quotas, credentials, and deployment effects against current official documentation before making changes.
• Do not treat generated examples as a substitute for environment-specific tests, security review, or user approval for destructive or costly actions.