I have not had Wifi on, but I have been playing music since 7:00 this morning and it is now 1:18 and I am at 91% of my battery left. I have no problems even when I am playing games and doing some social networking stuff at night with my battery getting hot. One thing I have is AutoKiller Memory Optimizer and have it set to aggressive. This seems to help keep the number of apps in the back ground open without being a task killer. It really seems to help on battery life as well.