I have gone through 3 3GS iPhones now... 1st issue was vibrate and once I got a replacement my battery life on it never lasted past noon. I replaced that one and my battery life still wont last past noon. Im thinking it might be an app thats messing it up. I will barely use it and it gets really hot and battery life drops at a constant rate, no matter how im using it, or using it at all. Please help, thanks.