I hv a iPhone 4S, and since i updated my IOS to 6.1.3, my phone gives me many problem
sms halfway hang
hang in dropbox
my bluetooth goes off and cant restart
my wifi cannot work
my hotspot works occasionally
too much headache, how to switch my IOS back to 6.1.1 ????
I tried to use the restore button in iTunes to factory settings, but it is still at 6.1.3
Anyone can help???