I updated an 8+ to ios15.3, this was a mistake. Something appears to have changed and I cant use it for more than a few moments without devloping a headache. Staying on it will get worse and worse. The display is 'displaying' differently, I think they've changed something about how the output is drawn on the screen, like a progressive / interlaced image sort of thing. Perhaps its also made a change to the refresh rate?
Even now after only moments of looking at the lock screen and going into settings to confirm the version I'm slightly dizzy. I find it unlikely that anything I had done in the moments before picking up the device was the cause of it, tomorrow if I dont try to use it I will feel fine, if I try to use it the problem will restart.
I've tried all the accessibility settings and reduce white point is on.
My regular 8 will remain on 14.8, I may try to purcase another 7 or 8 as a backup device as I've now lost mine.
(I preferred the smaller size of the normal 8 over the 8 plus which was my backup)
my ipad 6 (?) is on ios / ipados 13 as well, my fault for not updating it to 14 when I had chance, I dont think I can update it to 15, cant risk the problem as there is no way to roll back
It seems there is no escape from these problems. I am hoping that future ios15 updates may be more suitable? Either way there is no 'official' way for me to downgrade any of my devices to ios14