Mine can't even load iMessage without freezing.
The top was burning hot, the settings and messages app kept freezing to a blank screen until I had to look up how to force restart (volume +, -, then hold power). The battery was only at around 40%. I've never had an iPhone do that and I upgrade yearly..
Hoping it performs fine when it's cooled down and charged up to 100. The thing is I didn't even transfer phones, it was set up as new and I barely downloaded any apps. I'm guessing it was throttling due to syncing Messages and Photos.