Only 3 hours of Screen On Time?! topic

I only get 3 hours tops of screen on time. Seems too little, from what I've been reading. I have wifi, mobile data and GPS always on and mostly use 4g since I don't have wifi at work. Is this normal? What am I doing wrong to no get 5 or 6 hours of screen time like most people?

Some GSam battery monitor screenshots:

http://forum.xda-developers.co
http://forum.xda-developers.co

Cheers