As of June 24, 2013, the latest global renditions of the Samsung Galaxy S3 phones seem to be suffering from a rash of battery rundown and charging issues. These problems are being reported by people all over the world, so it does not appear to be specific to any single country or carrier.
The Samsung Galaxy S3 (and the new Samsung Galaxy S4) all have a lot of new features with the current versions of Android. There are so many features and settings in fact, that start by turning them off to really get a consistent experience with each Android phone I use.
1) WiFi = On whenever I can connect to WiFi. WiFi generally uses less energy then 3G, and since it is often quicker you stop actively using your phone/display sooner. If you cannot connect to WiFi, turn it off, as the searching for connections will use more battery!
2) Bluetooth = Off (unless in the car)
3) S-Beam = Off (I don't use this feature)
4) NFC = Off (I don't use this feature)
5) Keyboard settings (Vibrate on Keypress = OFF, Sound on Keypress = OFF)
6) Notifications are set to Off (no vibrations)…I only do audio alerts for Calendar, SMS/Text/IM, and Phone Calls.
7) All motions/gestures = Off
8) SmartStay = Off (seems like any feature to track your movement uses energy!)
9) Voice Commands = Off (I use the mic in Google Now for my voice stuff)
10) Multi-Window = Off (Again, another App/tool that I don't use)
11) GPS = Off (unless in the car and needing it)
12) No active wall paper, No animated/moving wall paper
13) No activity stream widgets other then Google Now (that and the Weather Channel App give me weather when I need it…it does not need to keep updating on it's own)
14) I've been prompted by the phone (not the apps) to sign into Facebook and LinkedIn…I don't see the need for an additional app running against these to use battery.
15) KIES Air/KIES over WiFi = Off (I don't use this feature)
16) Display Brightness is set at AUTO, though I frequently turn it to very low.
17) All home and auto chargers are updated to be at least 5-volts and 0.7amps (the newest from Samsung US are between 0.7 and 1.0 amps at 5-volts) Older chargers (especially car chargers), and some PCs just do not put out enough power to properly charge these modern phones. USB 1.1 & USB 2.0 = 0.1 amps or 0.5 amps depending on unrecognized vs. recognized device, while USB 3.0 = 0.15 amps or 0.9 amps again depending on unrecognized or recognized devices…so the moral here is use a USB 3.0 port, and make sure you have software or drivers installed to recognize your device and give you the optimal charge.
18) The only email clients I use are the built in ones (Exchange ActiveSync and Gmail)
19) The only IM clients I use are the Google Talk/Hangouts app, and the IM clients built in to things like Facebook, LinkedIn.
20) I don't run any app killers /task killers or special battery life apps…I know some people swear by them, and I understand the potential merits, but prefer a simpler approach with just less…It makes troubleshooting other things a lot easier!
Hope these help, and if I learn more, I'll be sure to share!