Improve your iPhone battery life. Here's how.

Get Rid Of Push Notifications You Don't Care About
This is especially important if you're someone (like me) who gets really excited about new apps, downloads them, and then never uses them again.

"Push notifications" are notifications sent by third-party apps straight to your phone through Apple's servers. When you have lots of them enabled, they can wear down your battery. If you don't need your phone to constantly check for updates from, say, your Stocks app, or that new social network you never use anymore, turn off the app's ability to send you notifications:

1. Touch the "Settings" icon.
2. Touch the "Notifications" bar. This should be the third bar from the top.
3. Look at the apps that are "In Notification Center." If you can do without up-to-the-second updates from any app you see there, touch that app's bar to be taken to the next screen.
4. Switch "Notification Center" from "On" to "Off" for each app you don't need notifications from.

Go Into Airplane Mode When Your Signal Is Weak
As I mentioned above, according to testing done by the scientists at iLounge, when your iPhone is using 4G LTE with a solid signal, its battery life is superb. But when it's using an older, slower network -- 3G or (gasp!) the EDGE network, it's likely using up battery life much more quickly. If you're experiencing super slow data speeds, it might be better to turn your phone to Airplane Mode, which shuts off all data transfers and generally means your iPhone isn't doing much. And when your iPhone isn't doing much, it isn't using much power.

You follow me? If you're not getting much reception -- or if you can go for an extended period without your phone -- you should set it to airplane mode.

1. Open the "Settings" app.
2. Switch "Airplane Mode" (it's the first setting!) to "On."

Turn Down The Lights On Your Screen
A super-bright screen is also a super-battery-sucking screen. Decreasing the brightness on your iPhone (and, really, anything with a screen) can help increase the amount of time the battery stays alive. If you can live with a dim screen, your iPhone will live for longer, too. (You might also want to turn off Auto-Brightness while you're there.)

1. Touch the "Settings" icon.
2. Touch the "Brightness" bar.
3. Move that bar to the left as far as you can handle it.

Lock Your Phone
When you put your phone down on the table, or in your pocket, the display probably doesn't need to be illuminated. iPhone owners should practice locking their phone when it's not in use (by pressing the slender silver button on top of the phone). You can also set the auto-lock feature to kick in after a shorter amount of time, which will (surprise!) lock the phone and turn off its display light sooner.

Turn Off Location Services For Apps That Don't Need Your Location
Does Facebook really need to know where you are all the time? How about Shazam or Pandora? You can choose which apps have access to your location in the Location Services section of the Settings:

1. Touch the Settings icon.
2. Touch "Privacy."
3. Touch "Location Services."
4. Don't turn off "Location Services" at the top of the screen. That stays "On."
5. Go through your apps one by one and determine which ones have to know where you are to function properly.

Note: Most apps that request access to your location, like Yelp or RunKeeper, really do need it to do their jobs. Facebook and Twitter, meanwhile, only need your location to put a GPS stamp on your posts, which not everyone is going to find useful or desirable.

Of course, if you're uncomfortable with disabling location on any of the apps listed, then don't disable location. But if you see that Fruit Ninja, or something similar, is using your location, it's probably safe to slice Location Services right out.

Turn Off Siri's 'Raise To Speak' Function
When the iPhone 4S first came out, many owners reported that "Raise to Speak," a Siri function that allows users to lift the phone to their ears to activate Siri, was causing battery drain. Unless you use it often, or find it useful (most don't!), you can turn it off for good:

1. Touch the "Settings" icon.
2. Touch "General."
3. Touch "Siri."
4. Slide "Raise to Speak" to the "Off" position.

Fetch, Don't Push, Your Email
You probably don't need to read each email the second it reaches your phone (unless you're a super important, time-crunched businessman or woman). When "Push" is enabled for your email, it does just that, forcing email from the servers onto your phone immediately. You can switch it to "Fetch" so that your phone is checking for new email less frequently. As the iPhone setting says, "For better battery life, fetch less frequently":

1. Touch the "Settings" icon.
2. Scroll down to "Mail, Contacts, Calendars." Select that screen.
3. Touch the "Fetch New Data" bar.
4. Turn off "Push."
5. Choose a schedule for how often you want your email refreshed.

The longer you wait, the less battery you'll use up. If you choose "Manual" and leave it up to your own brain to remember to check your email, you'll be saving lots of battery life (especially while you sleep).

Stop Checking For Wi-Fi All The Time
If you're walking around and not actively looking for a Wi-Fi hotspot, then turn Wi-Fi off in your settings to save a little bit of power:

1. Touch "Settings" icon.
2. Touch "Wi-Fi" bar.
3. Switch "Wi-Fi" to off.

Update Your Operating System Already
Whenever Apple pushes out an update to iOS -- the operating system that's running on your iPhone -- it usually includes features that will help your phone use battery life more efficiently. If you are on an older version of iOS, you may not be getting as much battery life as you could if you updated.

In order to check for an update:

1. Touch the "Settings" icon.
2. Touch "General."
3. Look for Software Update. If you see a number next to it, you have an update.
4. Follow the instructions here. For users with newer iPhones, iOS 6.0 is the version you want.

Download A Battery Improvement App
As a last-ditch effort, there are several apps in the App Store that claim to help with your battery life and guide you through the process of extending the time you get from a full charge. My favorite is BatterySense by electronics giant Philips: It's free and you can download it right here. BatterySense essentially analyzes your usage and shows you which settings are killing your battery and which ones you can tweak to make things last longer.

Other popular options include Battery Doctor Pro and Battery Life Pro; the intriguing Carat app, from the AMP Lab at UC-Berkeley, is also worth a look.