I've begun to notice that my screen isn't as responsive to tappings, as it once was (especially near the perimeter). I have searched through the 'Settings' menu, but could find nothing on screen calibrating. I am sure that there MUST be a way in which to achieve this. Is there?
I have often wondered about this myself - but there is no way to calibrate a (non-jailbroken) iPad screen. The lack of response to 'touch' can be a CPU response issue - i.e. the iPad's processor is tied up doing something and simply doesn't register the input from the touch screen controller IC (silicon chip) that's responsible for managing and controlling the touch screen.
Like several other 'issues' I've found that a complete 'off-on' power cycle (i.e. completely switching off, not just putting to sleep) often 'revitalises' the iPad - clearly recycling the iPad power gets to parts of the iPad that other methods cannot touch....
Tim
Scotland