I've been using the Sleep Cycle accelerometer-based alarm clock app for a while now:
But since very recently the app seems to be using up all of my battery overnight, which it didn't do before, and shuts down the phone. It also started to make my iPhone very hot to the touch in the morning.
Besides that, when the app is activated and I lock the screen (which I do obviously for security reasons) the app blocks all text message sounds, which is also bad.
So I was curious if there's any other app (paid or free) that could replace my current app without the drawbacks listed (excessive power, excessive heat, suppressing messages)