Turn on and turn off automatically.
You can set your smartphone, like BlackBerry, to turn off while you aren't using it for an extended period, like when you sleep. The data you receive when the smartphone is turned off automatically updates when the smartphone turns on.
Set backlighting to remain on for a shorter period of time, and lower its brightness.
For other tips click here: http://answers.techzim.co.zw/14389/tips-1-and-2-of-extending-the-battery-life-of-your-phone