Last night I plugged the iPhone 4s into the wall when it was at around 50%. When I got up in the middle of the night I looked at it and it was at 100%. I left it plugged in. When I woke up this morning it was at 95%. How could it lose power while still plugged in to the wall? When I got to work ½ hour later it was at 93%. From then on, everything I did took more power than I could have imagined. I'm not so concerned about the power drag when I am on the Internet or otherwise using the phone. Does the loss of power while plugged in sound like a serious problem, or is it just typical of the 4s, which seems to have battery issues?