Ever since I updated to 4.4.2 about a month and a half ago my battery drains insanely fast. (Eg. I'm 100% charged at 7 am when I get up to go to work. By my break at 11 am it's at 10%. All I used it for was one text message and to use the flashlight.) My phone seems to tell me the majority of the battery usage goes to "Andriod OS." I've had my s4 for about a year now. The battery wouldn't die that quickly would it?
Read more: Why is my galaxy s4's battery draining so quickly?