Build React Native apps with Expo | Codex use cases
Need
Routing
Default options
Why it's needed
Expo Router keeps navigation file-based and predictable, which helps Codex add screens and flows without inventing a custom routing layer.
use-cases/react-native-expo-apps.md +7 −96
11name: Build React Native apps with Expo# 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
245 [describe the app idea, target users, and the main workflow]Routing
25 6
7Default options
26 8
279 Requirements:[Expo Router](https://docs.expo.dev/router/introduction/)
28 10
2911 - Start with Expo Router and Expo-native project conventions.Why it's needed
30 12
3113 - Try `npx expo start` and Expo Go first before creating a custom build.Expo 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