I have had my S3 for about 6-7 months now and it has been working fine since about 2 months ago. Since then, my phone sometimes acts very strangely. For example, I charge my phone every night, so I know that my the morning, it is at 100% while it's plugged in because i can turn it on and see that. But sometimes, as son as I unplug the phone from the charger, the screen will light up and display the battery percentage as anywhere from 80-40% (i.e. the battery drained drastically for no reason right after I unplugged it from being at 100%). Also, occasionally, my phone would discharge in pocket so quickly that it can drop from 33%-16% in about 3 minutes. Both my lock screen and home screens are black backgrounds, the screen is at the lowest brightness possible, I always kill my background apps after use, I use Advanced Task Killer often, I use the app Juice Defender on aggressive use, and I have everything from bluetooth to GPS turned off (except WiFi when there is WiFi). This is very annoying because I wake up at about 6:30 every day and some days my charge only lasts until about 10:00. It is so strange to me that anything can discharge that quickly (I'm talking about 3% every minute). Please Help!!!