Filed under: Software, Hacks, Tips and tricks, Apple, iPhone
Extending your iPhone's battery
IntoMobile has a few good tips on how to extend your iPhone's battery life, and most of them involve the most obvious thing you can do to keep your iPhone running: cut down on any and all extra functions. They actually recommend to turn off 3G, but you don't have to go that far -- just by holding down the Home button, you can close any background applications sucking up juice. And by resetting your phone, you can do the same thing -- clear out anything running that you're not using.Actually, while I was in Los Angeles last week, I heard the great Leo Laporte mention a great tip on his radio show: turn off the "Ask to join networks" feature in the WiFi settings. If you're like me, you almost always know when there's a WiFi network around that you can use on your iPhone, and so it's pointless (and a waste of battery life) for the iPhone to be constantly searching for one. You can always flip it back on if you do want to do a little poking around, but leaving it off will significantly help battery life.
In fact, when in extreme trouble, you can go even farther and just switch the whole thing into Airplane Mode. It'll make your phone useless, but when you really need it -- out on a trip, or waiting to make an important call -- the extra battery time might make all the difference.
[via Apple Enthusiast]


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Reader Comments (Page 1 of 3)
dagamer34 said 5:12PM on 7-23-2008
I was really hoping Apple would have given us more customizable options for when 3G should be enabled or not.
Stuff that should have 3G enabled: Safari, YouTube, Mail attachements
Stuff that can live on EDGE: just about everything else.
Though, the only real problem is with Apps. Sometimes I want them to use 3G, other times I don't (even within the same app). Makes for an extremely complicated mess. I'm thinking that Apple should update the SDK to include a provision that would allow apps to turn on and off 3G (with a prompt like when asking for location). That might be a little better.
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david said 8:18PM on 7-23-2008
I have found that if you turn off location services, Im getting about 30-40% more battery left by the end of the day. Of course when you use maps, it turns it back on..but otherwise leave it off...it helped a ton.
David
tys said 5:24PM on 7-23-2008
I've got 3g off, but most of the time I just need wifi. I rarely need phone, edge, or gps. Especially at work where I have wifi, but no phone coverage. I wish there were a wifi- only mode. That would save tons of battery life, I bet.
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Flannel said 5:28PM on 7-23-2008
Put it in airplane mode, then turn wi-fi on in the settings.
I know that sounds too simple to be true, but it works.
FatMax said 5:48PM on 7-23-2008
If you turn on Airplane Mode and THEN swith wifi on, you are good to go in wifi-only-mode...
tys said 6:10PM on 7-23-2008
thanks Flannel and Fatmax!
That worked.
You are my heroes!
Has this always worked, or just in version
2.0?
Tys
PiperSon said 7:18PM on 7-23-2008
I am waiting for someone to release an app with just the wireless radio controls (3G/WiFi/GPS/Bluetooth) so that you can switch them on and off much more easily...
...please can someone write one?
MikeP said 5:14PM on 7-23-2008
Even if you turn off "ask to join", doesn't the phone still need to constantly search for your saved networks when you're accessing the internet? And while it will stop the annoying popups asking if you want to join an available network, does it really save any battery power?
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nz said 5:26PM on 7-23-2008
That was my question, too. I mean, I don't think I ever really liked having it pop up and ask if I wanted to use WiFi. But my impression was that if I turned that feature off, I would have to manually hop on the WiFi network at home. (I know, can't get much lazier)...
If turning it off saves battery and allows me to jump right on "known" WiFi stations, I can't imagine why it wouldn't default to off...
DistortedLoop said 5:40PM on 7-23-2008
Yes, you are correct; turning off ask to join does not turn off the WiFi, and does not keep the radio from scanning for networks, known and not known, it only keeps it from asking you if you want to join them.
The proper tip is to TURN OFF WiFi, and only turn it on when you want to surf at WiFi speeds and know you are near an access point you can use.
Personally, I'm happy enough with 3G speeds here in LA that I've stopped using WiFi even in my house.
That said, the battery life on the iPhone 3G is AWFUL, even with WiFi turned off. I'm only 6 hours into a 12 hour out and about day, and have had to plug the phone in for battery boost. Not that that's horrible, I mean how hard is it to dock it in the car charger or with the computer while at a desk? It's just a bit of culture shock compared to the first phone, which had bad enough battery life to warrant a $100 Mophie Juicepack for spare juice.
Jeremy said 5:42PM on 7-23-2008
I have turned this off, and have noticed a clear increase in battery life. That being said, I have also been using wifi both at work and in my office much more than 3g, so that might also be the reason.
w00t said 5:16PM on 7-23-2008
If you were really in a pinch and needed to save juice airplane mode is a waste (unless you really needed to keep the tunes pumping) so powering it off until you needed it would be the best bet.
Also, if you want to be sure you always have power and use your phone pretty heavily like me, an emergency battery (one that plugs into the dock port) in your wallet is a brilliant idea :)
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Jeff said 7:22PM on 7-23-2008
yeah, why the hell would you want to keep it in Airplane mode to save battery instead of just turning it off??
also, you could just carry a cable with you. :) but yeah, extra battery is nice if you're no where near an outlet of any kind.
lok cheung said 12:43AM on 7-24-2008
for me the "airplane mode" IS "turn off". because the iPhone is not just a phone, it is a pda for me. when i back home i forward the call to home line, turn on airplane mode and switch on wifi. i don't want to turn on and off everytime i need the iPhone for email, note or calendar
scw said 5:46PM on 7-23-2008
If you're going to use Airplane mode, why not just turn it off until you need it?
That will save the most battery power.
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Josh said 5:21PM on 7-23-2008
I was under the impression that iPhone apps never run in the background.
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Valerie said 5:44PM on 7-23-2008
Well something like aim doesn't alert you if you get an im and you're not on the app, except for sometimes vibrating, but then when you click on the app, it tells you who has imed you, instead of a text message going to your phone like you're mobile
DistortedLoop said 5:44PM on 7-23-2008
Only a few Apple sanctioned apps are supposed to run in the background (mail, SMS, phone, etc); others are not supposed to, but that doesn't mean they all behave and exit nicely.
I've gotten in the habit of holding the home button down to force quit some apps I suspect of not shutting down properly to see if it helps battery life. Be careful with this, though. I thought Safari was a culprit, so force quit it, only to find all my pages and stuff that are always there on a return to the application were gone. Other apps may lose data shutting them down this way.
christapher said 9:21PM on 7-23-2008
So is there any kind of feedback when you force quit it? I just tried holding it down for a few seconds and didn't seem like anything happened. I know stevesy made fun of winMo's task manager, but as an avid and obsessive user of iStat, I wish I had that functionality. Especially if some... uh... unorthodox apps end up on my Pineap... Apple iPhone that might not follow the 'no background process' rule.
Will said 5:43PM on 7-23-2008
I wish Bluetooth on and off wasn't buried so deep. I only need BT when i am in the car but I leave it on all the time for convenience.
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