Got the iPhone X a few days ago and noticed that sometimes framerate would tank in a game. It would go from 60 to 30 after a minute. I assumed this was due to thermal throttling but it isn't. I narrowed it down to raising and lowering the volume while in an iPhone X optimized game.
Try it out on Super Mario Run. Start playing and press the volume button and your framerate will be cut in half. Another thing that sets this off is switching from the Youtube app that playing a video to the game. Is this a iPhone X issue or developer issue?
Try it out on Super Mario Run. Start playing and press the volume button and your framerate will be cut in half. Another thing that sets this off is switching from the Youtube app that playing a video to the game. Is this a iPhone X issue or developer issue?