My app doesn't run when i sent the .apk after Building (Ai Companion works)

MIT App Inventor Help
1

Please help!
When i try the qr code with Ai Companion my app works perfect. But after Building when i try to sent the qr or try to run the .apk file that i download i see only a black screen...

What can i do?

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2

It could be anything but 9 times out of 10 it's because the App icon image has not been configured correctly:

Adaptive icons: Specify an app icon 512 x 512 pixels PNG format and the App Inventor Build Server will generate icons for every available icon size and shape needed for Android.

See:
https://www.professorcad.co.uk/appinventortips#TipsImages