I was using icleaner and it froze. So I removed it from the multitasking window (or whatever it is called) and went to the home screen and opened icleaner again. I noticed that my carrier was missing and my phone looked a little off. Then a few seconds later my phone just shut off and had the moving circle loading thing when your phone dies. I tried turning it on again and it said I had to plug my phone into iTunes. After I plugged it in it made me reset my phone.