I have noticed that my Galaxy S3 phone will go from 90% charge to ZERO (and shut off), between the time I go to bed and wake up in the morning. First, I use it mostly as a phone and TM device. Occasional browsing to check email and bank account. But I rarely, if ever use it to watch movies, or listen to music... at least so far. Most of them time, my phone will go a couple of days without needing charging. But I have noticed a few times that when I go to bed with a high charge (80% or better), it can be fully depleted by morning and powers off. I leave the phone locked but on, when I go to bed. I leave Wi-Fi on, generally but bluetooth and GPS are off. The phone is locked by pressing the side button. There are no apps running in the foreground. There may be tasks running in the task manager but I would expect those to suspend, when I lock the phone. None of the apps in the task manager are music or video apps that wouldn't be expected to suspend. Since this is only an occasional thing, I'm not sure what might be depleating the battery so quickly. Any ideas what might be running my phone down. It should be able to go throughout the night without running down, especially since I'm not watching movies or listening to music.