The iPhone 4S already has pretty good battery life, but if you plan to use it heavily, or to take it on vacation, you’ll want to know how to squeeze every last bit of power out of the iPhone.
Here is a collection of ways you can extend the life of your iPhone, without sacrificing your user experience.
If software tweaks aren’t enough, we have a few iPhone 4S accessories that will help you get better battery life, even though you can’t replace the battery on the iPhone 4S.
(Read: iPhone 4S Review)
The screen is one of the biggest power users on the iPhone, which means you should turn your attention to display brightness first.
To get there, hit up Settings and Brightness.
Here you can control the standard brightness of your display.
Turn Auto Brightness on to let your iPhone adjust to brighter and darker settings automatically.
This auto setting is the key. Without it, you will get frustrated by a screen that is too dim when you head outdoors. Auto brightness isn’t perfect, but it does help keep your screen viewable without using excess battery life.
The more email accounts and services you have syncing, the faster your battery life goes by.
If you have multiple email accounts on your iPhone 4S, go to Settings -> Mail, Contacts, Calendars and turn Push to Off when you don’t need the extra accounts syncing.
The best example is turning off work email accounts while you are on vacation or on the weekend. This can be a big battery saver.
Check Mail Less Frequently
If you don’t need to be notified of new mail the instant it is sent, you can turn off push and set mail to check for new messages less frequently.
Head to Settings > Mail, Contacts, Calendars and tap on Fetch New Data.
Scroll down and choose a time of 30 minutes or an hour to check for new email.
I choose to auto check every hour. This helps save battery life and lets me concentrate on projects without interruptions.
You can always check for new messages by opening Mail and refreshing by pulling down.
Put Notifications on Notice
Push notifications, like those from instant messaging apps eat up battery life. Turning off notifications will still allow you to get new messages when you open the app, you just wont get visual and audible alerts.
Some apps allow you to turn off notifications in Settings -> Notifications.
When you are in the Notification Center, tap on None for the Alert Style.
Others will require you to go into settings to turn off notifications in the app to put an end to battery using notifications.
This is another area where you have to make tradeoffs. I limit notifications from apps like Facebook and Tweetbot, but leave IM+ and Yammer on most of the time because they are essential to me.
Your best bet is to find what you can do without, and when.
Limit Lock Screen Notifications
Another tip is to avoid lock screen notifications for apps that send a ton of notifications. Every time you get a notification for a new email, your screen will light up, using up precious battery life.
Go to Settings -> Notifications.
Find the app you want to limit and tap on it.
Scroll down to the bottom and toggle View in Lock Screen to Off.
Turn off Bluetooth
Bluetooth is an easy way to connect to computers, cars and headsets, but if you don’t use it often you can turn it off to save battery life.
To turn off Bluetooth, head to Settings -> General -> Bluetooth and flip the switch to Off.
Even though I use a Bluetooth headset, I usually keep Bluetooth off, and turn it on when I am expecting a long call, or when I jump in the car.
Turn off WiFi
If you aren’t using WiFi, turn it off to save battery life.
To do this, go to Settings -> Tap on Wifi and then switch it to Off. This is also a good time to turn off Ask to Join Networks.
Even when you are not connected, the WiFi radio is constantly searching for WiFi locations. This is so that you can get connected fast, but also to help figure out your location.
When you browse on WiFi, you will get better speeds and better battery life than on 3G, so you’ll want to remember to turn WiFi back on.
Forget Location Based Reminders
The ability to have your iPhone 4S remind you to do something based on your location is amazing, but it comes at a price.
If you set a location based reminder, your iPhone will monitor your location until you reach the work, or home. This can cut into your battery life, so you should use it sparingly.
For example, I won’t be back at my teaching job for another week, so setting a location based reminder would drain my battery every day. Instead, I will ask Siri to remind me at a specific time, or to remind me to make a location based reminder.
These reminders are best for short times, such as on the way to work or right as you leave, if asking for a reminder at home.
If you are in poor coverage areas, and your phone keeps searching for service or switching between your carrier and roaming, you might be better off turning Airplane mode on.
This will turn off your WiFi, Bluetooth and 3G connectivity. This means you will not get any new messages, texts or phone calls, but if you are searching for service, you probably weren’t getting them anyway.
Go to Settings -> Toggle Airplane Mode to On
Don’t forget to switch this one back on when you get to better coverage. You might want to use Siri to set a reminder.
Auto Lock and Sleep Fast
Because the screen uses a lot of your battery life, leaving your iPhone 4S display on when you aren’t using it is leaving battery life on the table.
Set Auto-Lock to 1 Minute if possible. If you have your PassCode lock set higher, you can still access your phone without your PassCode, but the screen will turn off and auto lock after a minute.
Go to Settings -> General -> Auto Lock and choose 1 minute.
If you combine this with manually locking your phone when you are done with it, by pressing the power button, you will save a lot of battery life. Training yourself to turn the display off when you set your phone down or toss it in your pocket.
Limit Location Services
If you need to cut back further, look for apps that are using your location without the need to do so. Apps will tap into GPS and crowdsourced WiFi to find your location.
This is essential in Maps, but there are other apps like Facebook, and others, that use your location without the need to.
You can turn off all location based services, but that is likely overkill.
Instead, go to Settings -> Location Services
Toggle the apps you don’t want to use your location to off.
I recommend doing this sparingly, as many apps enhance your experience with location. If an app stops working as you expect it to, you might need to re-enable location services for it.
Restore Your iPhone
If you notice that you are getting bad battery life a few months after getting your iPhone 4S, you can restore your iPhone in iTunes to get better battery life.
Be sure that you have created a current backup, and then use the Restore button in iTunes to revert to factory settings.
At the end, restore from your most current backup, and you will have your apps, data and accounts — and hopefully better battery life.
Get a Battery Powered Case
If all else fails, you might need to get a case with a built in battery. The Mophie Juice Pack Air is the most popular iPhone case with a built in battery.
For $80, you can get a black, white or red case that includes a 1500mAh battery and offers easy removal. With this option, you get a nice battery boost, almost double the talk time, without adding significant bulk. This video below shows how long the Mophie Juice Pack Air can last, and gives you a look at the case.
I also like that this adds a MicroUSB charging port, so you can charge the case and your iPhone with a standard MicroUSB cable. This type of case is almost a necessity if you plan to take your iPhone 4S with you to a convention, conference or vacation away from outlets.