How to extend your iPhone's battery life

Step 1: Close apps

Exit out of applications when you're done with them. Leaving applications active will drain the battery even when the iPhone is in the standby state.

Step 2: Keep it cool

Keep the iPhone out of the heat -- such as in a hot car (especially avoid the glove box) or in direct sun. Apple suggests that you keep your iPhone as close to room temperature as possible (that's about 72 F, or 22 C).

Step 3: Not too bright

Lower your iPhone battery consumption by reducing screen brightness (go to Settings > Brightness > then move the slider as far to the left as you can while still being able to see everything).

Step 4: Turn off unused networking

If you're not using 3G access, data roaming or wi-fi, turn any/all of these settings off (go to Settings > General > Network and select options there).

Step 5: Pull the Bluetooth

Not using Bluetooth? Shut it off (go to Settings > General > Bluetooth).

Step 6: Charge in the car

Plug your phone into the car charger to conserve juice while you're driving and using the iPhone for music, calls, navigation or anything else.

Step 7: Shut down the vibes

Turn of the "vibrate" setting if you don't need it or aren't in silent mode (go to Settings > Sound > 2 vibrate options there).

Step 8: Skip the equalizer

Switch off the equalizer for song playlists (go to Settings > iPod > EQ).

Step 9: Plug into the port

Hook your iPhone into the USB port when you're at your computer to conserve battery power. This is also a great time to sync your device and download any new versions of iTunes or iPhone software.

Step 10: Try a battery boosting device

Get an add-on battery charger accessory, such as the RichardSolo 1800 for iPhone or Kensington Battery Pack and Charger for iPhone 1G & 3G. This device can reduce the load on your battery, and is helpful for long flights or other times when you can't recharge on the go.

Step 11: Lock it up

Lock your iPhone when you're not using it (click the top button for sleep/wake) so nothing happens if you accidentally touch the screen. You can also set the auto-lock go on after 1 or 2 minutes of no activity (go to Settings > General > Auto-Lock).

Step 12: Maintain your battery's health

Run your iPhone battery to empty and fully recharge it at least once a month. Apple says, "For proper maintenance of a lithium-based battery, it's important to keep the electrons in it moving occasionally. Be sure to go through at least one charge cycle per month (charging the battery to 100% and then completely running it down)."

For more tips on taking care of & using your iPhone, see:
Why the iPhone is the future of mobile