A:Answer Hey mkey,
I hope you are doing well.
This happens to me as well. So far, it has been just fine. It has not heated up too much, it stays within reason. Plus I have also experienced this when it was off the charger, as well. It's nothing that's not supposed to happen. If it gets too hot to touch, then that's another issue. In that case, the workload you have for this phone may be too much. It is just a mid-range, after all. Another reason could be an issue with your device, of course.
Cheers,
tallbencat