Hi, I have an iPhone 5S running iOS 8.1, but I have very fast battery drain. I have background apps turned off, most of notifications completely turned off, spotlight suggestions turned off, handoff turned and suggested apps turned off and frequent locations turned off! But my iPhone lasts only 3-4 hours of simple use like Facebook, listening my music library or chatting on iMessage. Here is my screenshot of battery usage, it says only 5 hours used (and the iPhone has plugged in since the last full charge) and my battery is 16%!!! Is it normal?? I have give it on apple service and they replace my device two times but the problem is still there. I have do many times restore and setup as new without restore from backup.