Originally Posted by
HDQDD
It works fine if you use passbook (and I assume Android's equivalent). Added bene is that the QR code is rendered larger. Personally I find max brightness on UA's app really annoying if I'm not in the process of boarding. I wouldn't be using the app for boarding anyway, I'd use passbook.
On Android (maybe also IOS?) you can tap on the QR code for a larger version (but then the screen only shows the QR code and literally nothing else until you tap again to return to the previous view)