I just updated my iPhone 5 to iOS 6.1. Since then my screen consistently behaves as follows: as long as I provide input to the touch screen (i.e. keep tapping / swiping across the screen) everything's normal. But as soon as I don't touch the screen for more than 2 seconds, it becomes totally unresponsive, not registering any touch input at all (home button still works). When I lock / unlock the phone it works again until the next time I let go of the screen for 2 seconds. A reboot doesn't help. What's worse: even a factory reset does not help. Any idea what else I could try apart from bringing the phone to an Apple store? From the symptoms I don't see how this could be a hardware problem, but then again it seems to be a rare issue, I did not find any other mentions of this on the web.