I have a solution for this(must be work)
1. First of all disabled bundled stock apps like chat on etc I have attached a screen shot of disabled apps on my s3
2. Off NFC android beam.
3.disable s voice( big battery eater)
4.must disable s memo and exchange mail
5.clear cache of all files and apps weekly
6.flip board users plz clear your cache routinely( this apps has a network bug that eat more battery in less time.
7. Set sync of apps like Google +,mail,wheather to 6 hours.
Screenshots are below.
Plz tell me after disabled these apps attached below that the tricks work or not
Sent from my GT-I9300 using xda app-developers app