Hi,
I have an iPhone 4 that will not turn on, no matter how many times I restore it nor which computer I use. Every time it restores it continues to go back to an endless boot loop, and occasionally goes to a kernel panic screen saying "Panic: We are hanging here...". My phone has never been jailbroken, but I did participate in the beta test of iOS 7 last year. However, when the problem started I was not in the beta versions of iOS 7; I was using the official release by then. I have tried putting it into DFU mode and restoring it, but no luck. We visited an Apple store and they were able to restore it with their own software and get it to turn on....but the phone crashed and went back to the loop a few hours later. Any help?