Originally Posted by TrueMetalGeek

You guys will laugh, but right now I sometimes use a car charger plugged into a DeWalt drill battery kept in my tool bag!
As I am going around fixing things I will plug the phone in for a little while here and there. It works. :-)

I have done zero mods for battery life.
I am kind of suspecting that leaving facebook open in the browser may be causing it to send background data every minute or so.