14 Tips for 3G iPhone Battery Saving (part 3)
10. Auto-Lock Sooner
You can set your iPhone to automatically go to sleep – also known as Auto-Lock – after a certain amount of time. The sooner it sleeps, the less power is used to run the screen or other services. Try setting Auto-Lock to 1 or 2 minutes.
Find it in Settings -> General -> Auto-Lock
11. Do Less Battery-Intensive Things
Not all ways to save battery life involve settings. Some of them involve the way you use the phone. Things that require the phone be on for long periods of time, or use a lot of system resources, suck the most battery. These things include movies, games, and browsing the web. If you need to conserve battery, limit your use of battery-intensive apps.
12. Sleep and Wake Less
Constantly putting your phone to sleep and waking it up will drain battery life. Of course these functions are common parts of using the phone, but you can also be judicious in your turning on and off of the phone and save battery life at the same time.
13. Buy an Extended Life Battery
If all else fails, just get more battery. A few accessory makers offer extended life batteries for the iPhone. If you need so much battery life that none of these tips help you enough, an extended life battery is your best bet. With one, you’ll get days more standby time and many hours more use.
14. Turn off Vibrate in Games
Playing a game with vibrate happening frequently is an unnecessary battery suck. If you can turn it off, turn it off.