Had this problem with my S5, now with my Note 4. I used Smart Switch to transfer my stuff over, apparently I transferred the problem too. My husband is using the S5 now, and the battery lasts him over 24 hours. I'm lucky to get 10, out of either phone. I've read every thread I can find about this, tried all fixes, and battery monitor apps. Nothing pops as being the culprit. Android system, OS uses the most resources. I have all features turned off like motion and gestures. Deleted apps like FB, messenger, Amazon. WiFi, GPS, Bluetooth always off. Limited to 1 background process. I've gone into everything like Google Apps and turned off everything that syncs, and location services. Killed every service and process I can. I only surf the web and read e-books. My husband is using YouTube and FB all day, yet his battery lasts twice as long at least, on the same phone. I basically can't use any of the features I got this phone for, or my favorite apps, and still have to charge twice a day. What am I missing here?