Previewing in Expo Go
Appsanic gives you a browser preview in the builder and an optional Android phone preview. Hosted iPhone preview is currently unavailable; use the browser preview on an iPhone.
Appsanic currently targets Expo SDK 54. Android needs the compatible Expo Go version linked below. The current iPhone App Store version supports SDK 57 and requires the phone and development server to use the same Expo account. Updating Expo Go does not make an Appsanic iPhone QR work. See Expo's compatibility announcement.
Set it up once
- On Android, install Expo Go for SDK 54 from Expo's official download page. The current Google Play version may not support this project.
- Open your Appsanic project in the builder and wait for the run to finish.
- Open Phone preview, choose Android, then select Start Android preview.
- When the QR is ready, scan it from inside the compatible Expo Go app.
- Wait for your app to load. If it fails, read the panel's error before retrying.
Opening the panel or choosing iPhone does not start a phone session. You can keep using the browser preview without installing Expo Go.
How it works
Appsanic starts a temporary phone preview from the latest finished version of your project, and the official Expo Go app loads it directly from Appsanic. Your phone does not need to be on the same network as your computer, and you never need to run any developer tools yourself.
The phone preview only uses a finished project version. It never sends partly written screens to your phone while the AI is working.
What works in Expo Go
Most of your app behaves exactly as it will in a store build:
- UI, styling, navigation, gestures.
- State management and information saved on your device.
- Supabase calls (database, auth, storage).
- Stripe Checkout (test mode).
- REST and GraphQL API calls.
- Local notifications.
What needs a real build
Expo Go carries a fixed set of native code, so anything outside that set only works in a build of your own:
- Apple and Google purchases inside the app. Buying things inside the app uses native code Expo Go does not carry. See Payments.
- Remote push notifications. Test these in a development or production build with the required credentials. Expo Go on Android does not support remote push on SDK 53 and later. Local notifications are separate and require device permission.
- App icons and splash screens. Those are baked into a build, so during preview you see Expo Go's icon.
- Widgets, share extensions, and other app extras outside the main app.
- Fully interactive maps. Maps that you can move and zoom rely on native code Expo Go does not include. The agent builds map screens with static map images, location search, and routes instead. Those work in the preview and on devices. Directions open in the Google Maps app.
- Real ads. AdMob ads only render in real builds. In the preview, the agent puts clear placeholder boxes where the ads will appear.
- Unusual libraries that depend on native code Expo Go does not include.
When you need one of these, create a real build. Use Publish to build and upload a store version through EAS, then install it from TestFlight on iOS or the internal test track on Android. See Publishing to the app stores. Appsanic does not currently build a custom Expo Go app for you. The store build is the supported route to native features.
Reloading
Expo Go has its own developer menu:
- Shake your phone. The menu appears with Reload among its options.
- Reload is the fix when state gets stuck or you want a clean launch.
Reload opens the current finished preview again. If the panel says the preview has ended, use Try again to start a fresh session.
When something isn't updating
If your phone seems stuck on an old version:
- Is a run still in progress? The phone preview intentionally waits for the run to finish. Let it complete.
- Shake > Reload in Expo Go.
- Close Expo Go, open it again, then scan the QR again.
- If the panel says the preview is unavailable, choose Try again once.
Appsanic does not push automatic updates to installed store builds. The preview session and a published build are separate things. See OTA updates.
Next
Now that you have seen your app on a real phone, send the code out to your own repo. Read Exporting to GitHub.