Sudden Rapid Battery Drain
A few months ago my battery lasted for 7 hours of screen = 3-4 days, and now less than 4.5 hours of screen = 1 day.
I don't have much apps installed and all of them are quite restricted, so there's no wake-up or anything like that. (WIFI/3G/GPS is usually of)
It could be because of malware (But antivirus says it didn't find anything) or intense battery usage in the past, but maybe I should just clean the system and reinstall the Rom. But I have much data on the phone and it would take a long time to backup ... so... what should I do?