Hello XDA members! I have recently bought a used Samsung Galaxy S4 SGH-I337M Telus/Koodo a few days ago on a website similar to Craigslist but better (Kijiji). I got it unlocked and updated it Android 4.3 not rooted.
Anyways, my phone battery is really bad. Yesterday night, the battery was at 47% when I went to sleep. No apps were running except my SMS app and WakeLock Detector. The wifi was turned off, the Power Saving Mode was on and the brightness was set to its lowest. This morrning when I woke up, the phone was at 19%, so it lost 28% in about 8.5 hours while in standby mode. I tried the app Deep Sleep Battery Saver but it doesn't seem to work very well. When I check WakeLock Detector stats, the Deep Sleep time is always at 0.0 seconds; therefore, my phone has NEVER entered in Deep Sleep mode