well to get maximum battery backup what i do is i keep location services off, brightness low not automatic, and keep syncing of email, fb, linked and other social services manual dont keep it on automatic update cos then they we will keep checking for new mail and utilise a lot of battery.i suggest you download battery from endless soft a great app to keep your battery stabilize and you ca monitor which app uses more battery and utilize it that way.
this app will also tell you the speed with which battery is discharging so you can keep a track of it. and tell you how long your battery will last. Here is the link Battery | Windows Phone Apps+Games Store (India)please provide the link....