My battery life is better since I updated to 5.1. I have a 4s on ATT. I usually charge every night while I'm on the computer, and take it off when I go to bed. I typically go to sleep about 2-3am and then leave for work about 10:30a. Before 5.1, I would typically have 88-90% battery when I left, now I have 94-96% when I leave. I leave WiFi on all the time, I use the clock on my phone as my alarm, and I have Gmail push email, and I leave news and some game notifications on as well. Sometimes I will also update apps, I'll start the update then go to sleep. I would love not to have to charge it everyday, but I still do as I don't know what the day will bring. Sometimes I'm down to 60% when I charge, and sometimes I'm down to less than 20%, but I charge everyday whether I need it or not. I hope that's okay.