Screen touch sensitivity

[ganguy]

What factors affect the way the screen responds to finger touches/taps/presses? I find that sometimes it won't respond at all to a touch and other times it seems to have a mind of its own, changing screens seemingly without being tapped. This seems to be independent of the app or program in use at the time.
I notice something similar on my wife's Tab2.

 

[anon(10181084)]

Greasy screen? Try cleaning it with some screen spray and soft cloth.