Recently, when standing in a field at Glastonbury, the idea came to us – was it really possible to make your iPhone battery last for several days? Well yes it is, as long as you completely strip down the power-sucking features and follow a few simple tips. Keep an eye on how long your iPhone typically lasts by going to Settings > General > Usage.
And, although this is not completely a power-saving tip, before you leave it's always best to make sure you have the latest software installed: Apple is always working on little fixes to improve your iPhone's power savings.
1. Keep it cool
Seriously. Don't put your phone in the sun. Don't leave it in a hot pocket. Battery life is lowered by heat and you should store your iPhone in temperatures less than 35 degrees centigrade – below 95F. As close to room temperature as possible is best for use.
2. Don't use power-sucking apps you don't need to
Minimise your app use, especially if it's a game, stuff that sucks data (hello, Facebook) or uses GPS. Not only does some of the fun stuff suck power, it can also stop the auto-lock coming on.
3. Turn off 3G
So there we were, in our field, with little data coverage (thanks O2). So what did we do? Turn off data, that's what. If you haven't got it, there's no point in wasting juice looking for it. Settings > General > Network and slide Enable 3G to Off.
5. Don't fetch
Set the common apps to only fetch data when you want them to. Set Mail, Contacts and Calendars to only fetch data Manually. BE WARNED - if you have MobileMe, it's dangerous to set the auto-check to Manual, since the much-vaunted Find My iPhone won't work.
6. Don't make long calls
Or don't make any calls. Sounds like the stupid filler tip, but if you do make calls (and you probably do, as that's almost certainly what you're conserving battery for), just keep 'em short.
7. Lock it up
iPhone not in use? Make sure you lock the screen and set the auto-lock to a minute in case you leave it unlocked.
8. Don't use the GPS
Minimise use of it (such as in Maps or turn-by-turn sat-nav) and disable it: Settings > General > Location Services. If you're lost, ignore this advice.
9. Turn it off when you don't need it
Sleeping? With all your mates anyway? Then turn your phone off. Bit pointless if it's for 10 minutes, but if it's hours, it will add up.
10. Disable Wi-Fi
Nowhere near a wireless network? Go to Settings and slide Wi-Fi- to off. However, if you are going to be doing a fair amount of data browsing and you are near a wireless network, it will be better for your battery to use this than the thirsty cellular signal.
11. Turn off Bluetooth
Likewise, make sure Bluetooth is off. And keep it there unless you use accessories: Settings > General > Bluetooth and slide Bluetooth to Off.
12. Push off
Not many apps use push notifications, but in the future this will have more of an effect on your iPhone's battery life as more start to. Settings > Notifications and slide Notifications to Off – only visible if you have relevant apps installed. Apple says this won't stop the apps receiving data when the app is actually open though, so be careful, unless you've disabled data in other ways. Equally you need to turn off push mail (MobileMe, Microsoft Exchange). Go to Settings Mail, Contacts, Calendars > Fetch New Data and slide Push to Off.
13. Turn it down
Refrain from employing the speaker for music playback and turn down the volume - louder playback can make a difference, even with the headphones. Set the phone to silent on the side.
14. Dim your screen
Turn off auto-brightness and whack the brightness down as low as possible. Especially effective for many of us, as it's the supreme brightness that's one of the things that makes the iPhone screen look terrific, so it's usually very bright as a default.
15. Go airplane
If you've got very little coverage, you can't make calls anyway. If you're going to be in a coverage lowspot for a little while, turn on Airplane Mode. It makes a serious difference, since your handset won't be continuously searching for a network signal. This is one of the biggest drains of battery life on any handset.
Liked this? Then check out Android vs iPhone: the ultimate platform war?
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