I recently got a galaxy S4 about 2 weeks ago, and the phone is great, but one problem I run into frequently is the battery life. It runs out way too quickly, and even when I'm not using the phone, the battery drops. Yesterday, I fully charged up my battery and left it overnight, and the next day, I woke up and found out that 20% was drained. I have no idea what is draining all this battery, and I have turned out every feature I don't use. Does anyone have any tips to increase the battery life?