Hard to say exactly how much, I surfed the web, played some games, streamed a lot of music, made some calls. Syncing and everything is all on, email is checked every hour, running Smart Actions all the time. It has a 2,500 mAh battery (almost double the capacity of the iPhone 5) which gets about 11 hours of continuous video playback (who the hell watched 11 hours of video on their phone though?), which gives it better battery life than most tablets. I do have very strong 4G LTE here too, never in airplane mode or anything like that.