i have an iPhone 4s and installed iOS 7 beta 2 today. it did not run perfect though, i couldn't download things from the app store for starters. i went into settings and update OTA to beta 3 and leave it there to download. but when it finishes downloading and installing, it will just stays at the apple logo when booting, then shows a dark screen, screen still lit, then boot again. it repeats itself until the battery dies out, even when it's plugged in. i tried again when i let it die out without plugging in and it still does the same. I've tried to put it in dfu mode by holding both home and lock and release lock to no luck. i have no idea what to do to get iTunes to recognise the device and restore it to a previous version. can anyone help me with what i should do in this case to get iTunes to recognise it again for recovery?