I usually use my ipad in landscape view and after awhile surfing the top left corner isnt touchable. The back button works though. Its only in safari the menu works fine. I have to restart my ipad for it to go away. Also if i touch in an area wich works and then move my finger to the nit working area it works. But when i lift my finger and directly place it in the non working area it doesnt work again. Anyone else had this problem? This has happened 3 times in a week now.