Charged my S4 I9505, rooted, to 100% last night. Went to bed at 00.30, I only then disconnected the charger.
Kept the phone next to my bed for the alarm-clock set at 7.30.
When that alarm went off, I looked on the phone, energy was now 35%.
To me this is ridiculous. I did not make any calls (unless during sleep-walking) etc.
BlueTooth was OFF
Wireless was OFF
I run Advanced Task Killer every 30 minutes with a 'Save' Kill Level.
... I don't get it.
It has the original European OS on it (4.3), I only added a couple of extra applications like
DropBox and Archos-video-player.