Owners of iPhone XS and iPhone XS Max are facing a strange stutter issue while getting back to the home screen from any App, which is usually done by swiping up from the currently open App to get to the home screen. Here the transition animation is stuttering after the screen remains idle for 10 seconds and users are frustrated to observe it since a few months now.
The issue has been persisting since a while now and Apple has not bothered to do anything about it. May people have also made social media accounts to complain about the issue whih has also failed to catch the eye of the company.
9to5Mac explained how the stuttering takes place in the video:
If you look closely at the demo video above, you can see how the iPhone XS drops a couple frames in the time it takes for the app to shrink back down into its icon. At full-speed, your eye perceives this as a very slight stutter. We have compared side-by-side with an iPhone X using a slow-mo video and the XS misses a frame of animation very consistently, whereas the year-old X renders correctly.
The frame drops don’t happen if the user has been actively using the phone, there seems to be a timeout of about ten seconds. After that wait, the first interaction lags behind the user’s finger … and then catches up. There is speculation that in the A12’s chip transition out a low-power state, it cannot keep up with the initial touch. However, neither the iPhone XR — which features the same A12 chip — nor last year’s iPhone X experience the same problem.