Ever since I got my 3Gs swapped out at apple I've noticed my screen protectors wont stay put. I have used a Zagg and a Antiglare and I notice them shifting off to one side or another over time. Also if I try I can slide them from side to side with a little force. Its like my screen on my 3Gs is greasy or something. I tried cleaning the screen and reapplying but they always slide a bit, never had this issue with my 3G and I don't think with my original 3Gs either. Anyone else having this issue with their 3Gs??