1name: Build React Native apps with Expo1# Build React Native apps with Expo | Codex use cases

2tagline: Go from a mobile-app idea to a working Expo app with the dedicated plugin.

3summary: Use Codex with the Expo plugin to scaffold React Native apps, stay

4 inside Expo Router and Expo-native package conventions, test quickly with Expo

5 Go, and move to dev clients or EAS builds only when the app needs them.

6skills:

7 - token: expo

8 url: https://docs.expo.dev/skills/

9 description: Use Expo-authored skills for Expo Router UI, native-feeling

10 components, data fetching, dev clients, deployment, upgrades, modules, and

11 Codex Run action wiring.

12bestFor:

13 - Developers who want to prototype or ship a React Native app with Expo before

14 reaching for native IDE workflows.

15 - Expo Router projects where Codex should follow Expo conventions for routing,

16 UI, package installs, builds, and deployment.

17 - Developers that need to migrate a web app to a mobile app.

18starterPrompt:

19 title: Build the Expo App

20 body: >-

21 Use the Expo plugin to build a React Native app with Expo for this idea:

22 2 

3Need

23 4 

24 [describe the app idea, target users, and the main workflow]5Routing

25 6 

7Default options

26 8 

27 Requirements:9[Expo Router](https://docs.expo.dev/router/introduction/)

28 10 

29 - Start with Expo Router and Expo-native project conventions.11Why it's needed

30 12 

31 - Try `npx expo start` and Expo Go first before creating a custom build.13Expo Router keeps navigation file-based and predictable, which helps Codex add screens and flows without inventing a custom routing layer.

32 14 

33 - Use `npx expo install` for Expo packages so dependencies stay compatible.

34 

35 - Use native-feeling UI patterns for navigation, forms, lists, empty states,

36 and loading states.

37 

38 

39 Deliver:

40 

41 - the working app slice

42 

43 - the run command

44 

45 - the verification path you used, including Expo Go, device, simulator, dev

46 client, or EAS

47 suggestedEffort: medium

48relatedLinks:

49 - label: Expo plugin

50 url: https://docs.expo.dev/skills/

51 - label: Expo MCP Server setup

52 url: https://docs.expo.dev/eas/ai/mcp/

53techStack:

54 - need: Mobile framework

55 goodDefault: "[Expo](https://expo.dev/) and [React Native](https://reactnative.dev/)"

56 why: Expo gives Codex a managed React Native path with fast iteration,

57 compatible packages, and deployment tooling.

58 - need: Routing

59 goodDefault: "[Expo Router](https://docs.expo.dev/router/introduction/)"

60 why: Expo Router keeps navigation file-based and predictable, which helps Codex

61 add screens and flows without inventing a custom routing layer.

62 

63## Start with Expo Go

64 

65Expo is a strong default when you want Codex to move from a mobile-app idea to a

66tested React Native app. The useful loop is `expo start` first, Expo Go

67on a device next, and then a dev client or EAS build only when the app needs

68custom native code, store distribution, or a capability that Expo Go can't run.

69 

70That keeps Codex focused on the app workflow instead of spending the first pass

71on native IDE setup, simulator setup, provisioning, or build configuration.

72 

73## Use the Expo plugin

74 

75Expo published an [Expo plugin](https://docs.expo.dev/skills/) that gives Codex Expo-native guidance for Expo Router, native UI, forms,

76navigation, animations, data fetching, NativeWind setup, Expo modules, dev

77clients, deployment, upgrades, and Codex Run action wiring.

78 

79Use it when Codex is building new Expo screens, adding packages, wiring API

80calls, preparing a dev client, or getting an app ready for TestFlight, App

81Store, Play Store, or EAS Hosting.

82 

83Optionally, add the [Expo MCP Server](https://docs.expo.dev/eas/ai/mcp/) when the task needs current

84Expo documentation lookup, compatible package installation, EAS build and

85workflow operations, screenshots, simulator interaction, React Native DevTools,

86or TestFlight data.

87 

88## Iteration process

89 

90 

91 

921. Ask Codex to inspect the repo and confirm whether it is a new Expo app or an

93 existing Expo project.

942. Start with Expo Router and Expo Go, and use `npx expo install` when adding

95 Expo packages.

963. Ask Codex to build one complete workflow with native-feeling navigation,

97 loading states, empty states, and error states.

984. Verify on the fastest available path, such as Expo Go on a device or a

99 simulator, then move to a dev client or EAS only when needed.

100 

101 

102 

103## Suggested follow-up prompt