Hello delboy, I have always a minimum of 4 hours SOT
I can do 5 or more hours SOT in about 15 hours standby, or 4 hours SOT in 40 hours standby, whether to use just the phone.
Use as much as possible the stock applications
In Google Account remove unnecessary synchronizations
If possible, use wi-fi, data network consumes much
I work in the office, the brightness is manual on my phone, -50%
often close the RAM
Grant permits for the automatic startup applications only necessary
Charge the phone when is off
If your phone has micro sd, verify that not one problem, my brother had problems, 1.30 minutes SOT, micro sd card always worked. Removed and replaced, problem solved
I removed all the vibrations, keyboard, click clok etc.
My English still not good