Installing an app through TestApp.io requires two steps: install the TestApp.io mobile app on your device first, then use it to install the release. Most installation problems fall into a few common categories—use the sections below to find your issue.
iOS Installation Issues
1. Developer Mode not enabled (iOS 16 and later)
iOS 16 and later requires Developer Mode to be enabled before installing apps outside the App Store.
2. "Untrusted Developer" prompt
After installing the app, you may see "Untrusted Developer" when you try to open it.
Go to Settings → General → VPN & Device Management.
Find the app's developer certificate and tap Trust.
Open the app again.
3. UDID not registered in provisioning profile
If you're trying to install an Ad-Hoc distributed app and it won't install, your device UDID may not be included in the app's provisioning profile.
Ask the app developer to add your UDID to their Apple Developer account and rebuild.
To find your UDID: How to Get Your UDID
For developers registering UDIDs: Add UDID to Apple Developer Account
4. Provisioning profile expired
Ad-Hoc and Enterprise certificates expire. If you get an installation error on a previously working build, the provisioning profile may have expired. Contact the app developer to renew and re-distribute.
5. Install fails on iPad
Safari on iPad may switch to desktop mode, causing the install page to not trigger the native install prompt.
6. Google Advanced Protection program
If you have Google Advanced Protection enabled on your Apple account, app installation may be blocked.
7. Use Safari, not Chrome
iOS requires Safari to trigger the native app install prompt. Chrome and other browsers on iOS cannot install IPA files.
Android Installation Issues
1. "Install unknown apps" or "Unknown sources" blocked
Android blocks installations from outside the Play Store by default. You need to allow installs from the TestApp.io app.
See full steps: Troubleshooting APK Installation on Android
2. "Parse error" or "App not installed"
This usually means the APK is incompatible with the device. Common reasons:
The APK targets a newer Android version than your device runs.
The APK was built for a different CPU architecture (arm64 only, but your device is armv7).
The file was corrupted during download — tap the release link again to re-download.
3. Google Advanced Protection
4. Previous version already installed
If a previous version of the same app is already installed with a different signing certificate, Android will refuse the install. Uninstall the existing version first, then install the new one.
Common Issues (iOS and Android)
The install link not working
Share links may be password-protected. Check with the person who sent you the link.
The link may have expired — contact the app developer to send a fresh link.
Make sure you have the TestApp.io mobile app installed before opening the link.
App installs but crashes immediately
The release may have been built with a debug configuration not intended for your device. Contact the developer.
Try uninstalling and reinstalling via the TestApp.io app.
Not receiving installation notifications
Make sure notifications are enabled for the TestApp.io app in your device settings.
Check that you have been added to the correct app and have the Tester or Guest role.
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