Troubleshoot app preview

Last reviewed: September 27, 2026

Start with the message and where it appears: on the platform or on your phone. Follow the matching case below.

1
Check the Expo account
If you see “You need to be signed in…”, follow Connect Expo and save a personal token for the intended account. Signing in to the Expo website alone does not connect the project.
2
Match the account on your phone
Open Expo Go and sign in to the same account. Different accounts block opening on a physical iPhone. See Expo’s sign-in error guide.
3
Refresh QR
After changing the token in “App publishing”, return to preview and click “Refresh preview code”, or “Start QR preview” if it has not started. Wait for preparation and scan the new code. If the error persists, create a new access token and reconnect.

The spinner continues or preview could not start

Initial preparation can take several minutes. The counter shows time since the attempt started. The message changes after 60 seconds, and a “Retry” button appears after 180 seconds while preparation continues. Server-side tunnel timing starts after requirements are installed; see timing details.

1
Read the platform message
You may see a message saying app preview could not start and asking you to check the account connection, retry, or use direct preview. Preparation, server startup, or the tunnel may have failed. The interface does not expose the detailed timeout cause.
2
Retry after a delay or error
When the counter reaches 180 seconds, you can wait or click “Retry”. The button also appears if the request fails. Check the Expo connection and the account on your phone if the error asks you to. You can switch to “Direct” to try the app while the tunnel is unavailable.
3
If it keeps failing
Send support the project name, start time, elapsed time, and error text. Do not send your access token. Repeated clicks or account changes will not resolve a tunnel connection problem.

The project is busy or identity setup is pending

1
Wait for the active task
A message saying the app workspace is busy means another operation is editing the app. Wait for it to finish in the chat. If identity preparation is pending, wait for that to finish too.
2
Try preview again
Click “Retry” after the task finishes. If the message persists, contact support; avoid starting repeated edit requests to resolve a waiting message.

The phone is on another network or the link will not open

1
Check internet access
The tunnel supports a different network or mobile data. Open a normal website on your phone to check connectivity.
2
Use the current code
Click “Refresh preview code” and scan the code currently shown. Avoid an old screenshot after restarting preview or changing accounts.
3
Try another connection
If a work or school network blocks the link, try another network you are allowed to use. If the link fails on multiple networks, try “Direct” and contact support.

Expo Go or the browser does not support a feature

1
Check compatibility
If Expo Go asks for a compatible version, use the appropriate installation link in the panel. Send the incompatibility message to the assistant if it persists; older projects do not necessarily work with every version.
2
Identify the failing feature
If the browser version fails, try QR after connecting your account. If Expo Go also cannot support the feature, ask the assistant to explain alternatives. Standalone builds and store uploads are currently paused.