Mine is not responding properly on very bottom part.
For example, I can't use very bottom line of keyboard.
Also, I tried everything to fix it except going Apple store.
I did reboot, reset, restore and updates, but it was not fixed.
Therefore, I'm planing to go to Apple store.
I'll tell you when I come back.
mine lost a complete row just above the bottom 4 buttons... Dead zone was equal to the size of the normal icons and prevented me from text messaging... I made an appointment with the Apple store.. went it and got a new one.. Was in and out with a new phone in probably 30 minutes