Thanks, Great TipThere is no full screen setting on iOS 5 (though I hear there is one coming for iOS 6...). however, I found that one of two things works for me when viewing a video. (1) I double tap the video and it sometimes fills the screen. Or, (2) if you reverse pinch the video (press two fingers on the video area, then spread them apart) it may sometimes go to full screen.
The second option works best for me. I hope this helps.
Marilyn