So like many I've had problems with battery life on the 4S. My issues got a bit better when following a method of restoring that someone else posted. This was when I was on 5.0. After that, I got about 5.5-6hrs usage. When 5.0.1 came out, I immediately noticed a drop in battery life. I would get about 4.5, and over the next few weeks that degraded to about 3.8hrs. I just tried the method I used before on a fresh install of 5.0.1, full file not OTA, and my battery is doing much better. Yesterday I got 5.75hrs battery, and today I have 50mins usage 5 hrs standby and am at 91%. The method was to 1) Back up phone to computer 2) Restore in itunes 3) When the restore from backup screen shows up in iTunes, and with the phone still connected, go through the setup process on the phone itself, selecting "Set up as new iPhone" 4) Restore from backup in iTunes (click "Next", you should be on the restore screen still on your computer) Doing it this way, for whatever reason, has resulted in much better battery life for me, now 2 cycles in. Not sure if the OTA update caused some issues or what, but so far so good.