11. Do Less-Battery-Intensive ThingsNot 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 LessConstantly 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.
If all else fails, just get more battery. A few accessory makers like mophie and Kensington 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. iPhone 4S & iOS 5: Turn Off Other Location Settings
Use this tip if your iPhone 4S or devices upgraded to iOS 5 are burning through battery life too quickly. It's probably a software bug, so Apple may fix it and this tip may go away, but in the meantime, here it is.
A number of additional location services introduced in iOS 5 seem to be draining battery too quickly. Turn them off and you should regain some battery life.
Find it in Settings -> Privacy -> Location Services -> System Services -> Turn off Diagnostics & Usage, Location-Based iAds, and Setting Time Zone
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