...while other devices could simply crank up the brightness of the whole display. I personally wouldn't mind, as long as the QR code is then readable (or rather

...while other devices could simply crank up the brightness of the whole display. I personally wouldn't mind, as long as the QR code is then readable (or rather, scannable) outside in the sunshine. I have a public transport app that does this when you show your ticket to be scanned.