I upgraded to jelly bean the other day with the kies software. All seemed fine initially however as soon as I unplugged my phone from the computer and then unlocked the screen, the touch screen calibration was off. When I touch the lock screen and don't move my finger it sees exactly where I'm touching however as soon as I move my finger it jumps to the top of the screen. In an effort to fix this issue, I have enabled the developer feature which shows me where the touch is being read by the phone. Sometimes I can just restart my phone but then if the screen locks, when I unlock it again, it's off again unless I plug it into kies again. I am getting an "error io exception no root permission" message that seems to precede the problem.