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Preview your app in the browser and on your phone

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Select “App” in the face control, then open the “Preview” tab. Use “Direct” inside the browser or “QR” to open the app on your phone with Expo Go.

Direct preview

  1. 1

    Select “Direct”

    Click “Direct preview”. This preview does not need an Expo account connection or an app installed on your phone.

  2. 2

    Wait for preparation

    A web-version build message appears, then the browser displays your app in a phone frame. Initial preparation can take several minutes; there is no guaranteed fixed duration.

  3. 3

    Test and refresh

    Choose an iPhone or Android frame and try navigation. After editing the app, click “Regenerate” to show the new version.

  4. 4

    If preview fails

    Read the message and click “Retry”. If a phone feature cannot run in the browser, connect Expo first, then click “Try via QR”.

Direct preview is a browser version. Phone features may differ or be unavailable. Expo Go also supports a limited set of features; opening a QR code does not prove that every feature works or that the app is ready to publish.

Connect Expo before QR

Connect your Expo account to the project first, then sign in to the same account in Expo Go. This is required on a physical iPhone: missing or mismatched sign-in can block opening with “You need to be signed in…”. A visible QR code alone does not prove the connection works. See connection steps.

  1. 1

    Install Expo Go and sign in

    Use the installation link for your device in the QR panel. Sign in with the Expo account connected to your project.

  2. 2

    Select “QR”

    Click “Start QR preview”. Saving a token through “Connect preview account” starts QR preparation automatically.

  3. 3

    Wait for the server and tunnel

    A server and tunnel preparation message appears with an elapsed-time counter. The message changes after 60 seconds, and a “Retry” button appears after 180 seconds. Follow the steps below.

  4. 4

    Open the code on your phone

    Once QR appears, scan it with the iPhone camera or the Expo Go scanner on Android. If you opened the platform on the same phone, click “Open in Expo Go”. If opening fails, see app troubleshooting.

How long does server and tunnel setup take?

Preview may return quickly when a connection is already ready. First-time setup can take several minutes. The code defines stopping limits, not a measured average, so “one minute” is not a promise.

  1. 1

    Watch the elapsed time

    The counter starts when you start QR preview. During the first 60 seconds, a message says the app server and tunnel are being prepared. Leave preview open while setup runs.

  2. 2

    After 60 seconds: wait for the progress message

    The message says the tunnel is still being prepared and may take up to 3 minutes. This is guidance; first-time setup may take longer while app requirements are installed.

  3. 3

    After 180 seconds: wait or retry

    The message says preparation has exceeded the expected time and the attempt is continuing. A “Retry” button appears while you wait. Click it to reconnect and follow preparation. The counter may retain the previous elapsed time if the same preparation job is still running. You can also choose “Direct” to try the browser version.

The 60- and 180-second messages follow the interface counter from the start of the attempt. They do not mean the server has timed out. Preparation continues after 3 minutes until a result or error appears.

Installing app requirements comes before waiting for the tunnel. Installation stops after about 10 minutes without output or at a 45-minute limit per attempt. It may retry once after output stalls. These are safeguards against hanging, not normal waiting times.

After the server starts, the system checks the tunnel every 5 seconds. Tunnel waiting stops after 3 minutes without log progress, or after 15 minutes even if progress continues. Checks can add some time around these limits. Total preparation can exceed 15 minutes because installation happens first.

“Retry” appears after 180 seconds of waiting and when an error occurs. Once QR is ready, you can use “Refresh preview code”. If waiting persists or errors recur, send support the project name, start time, elapsed time, and message, without your access token.

Your phone and computer do not need to share a network; the tunnel works over the internet. This is a temporary preview link, not a store release.