iMessage extension showing empty screen

Question

I created an iMessage extension. When I install it on one phone (via Xcode), everything works fine. Same with simulator.

When I attempt to connect a friend's phone and launch the app, it shows a blank screen. I can't find a crash nor other information in the Xcode console nor the macOS console.

I'm guessing the device is either too old (iPhone X), or the app is crashing on this phone for some reason.

Any idea what's wrong?

Answer 1

You must trust the developer of the iMessage extension on every device you want it to run:

1. Settings > General > Device Management > (Developer App)
2. Trust
3. Then try running the extension again.

You can get more details at Apple's article: https://support.apple.com/en-us/HT204460