Furthermore, 2G doesn’t support simultaneous voice and data. Therefore, if you’re attempting to, for instance, use a headset to talk on the phone while navigating with the Maps application (as one might commonly do whilst driving), Maps will cut out if you try to take a call, since the maps depend on internet connectivity to load.

While BT and WiFi are usually unnecessary, killing off the 3G for the sake of battery life, is honestly pretty damn stupid. In my area, the 3G network is around 5 times faster than the 2G on average in terms of data speed. You may get a few more hours of use, but you’ll waste far more time waiting for stuff to load than you’ll save by avoiding a recharge.

Regarding Wi-Fi and 3G, the 3G radio uses WAY more power than the Wi-Fi radio. The 3G one operates (I think) in the 1W range (to send a signal all the way to the radio tower) vs. the Wi-Fi which uses milliWatts and transmits 30 to 50 feet. You should turn off the setting about asking you to join networks because it’s annoying. But I don’t think the phone will ask about networks unless there is an app that is hoping to perform an update at that time. More on that below.

Meanwhile, the GPS is not operating unless you have an application running that is requesting location services from the GPS. Therefore, turning off location services doesn’t help you at all. The one area this might help is if you are running the maps app (for example) and you let the screen timeout/lock on its own. In that situation I am not clear on whether the maps app is still running or whether it’s sleeping. So I always quit the maps app when I am done with it for a while, since it and others all start up very quickly. But personally I think the app is asleep and so is the GPS radio …

Regarding force-quitting applications, that definitely does exist in the iPhone, it’s right there in the manual for crying out loud! You force quit an application if it’s hung, wedged, stuck, non-responsive. That’s rare but it does happen, and the way you deal with it is by holding down the Home button for 10 seconds or 15 or whatever it is, and then the app goes away and you end up back in the home screen. What “force quit” does to a normally responding application I do not know, except that it definitely does force quit it too. The question is, When you start it back up does it just restore itself to the same state using some save/restore mechanism? I have had the maps app in a weird state on more than one occasion where quitting and force quitting had no effect, and a reboot of the entire phone was required.

Finally, the two most effective ways to preserve battery life without disabling everything that’s good on the phone, is to reduce the number of checks for email (so turn off Push and set your Mail update to 1 hour or manual) and turn down the screen brightness. When you turn on your phone (wake it up from sleep, that is) and enter the mail app, it checks for mail then, regardless of your update frequency. The guy running active sync might be able to run active sync without having pushed turned on. There is no reason for your phone to be getting updates immediately, unless you are relying on those updates in a timely fashion. I bet you can just set it to manual or every hour and still have all the other features of active sync.

Taking pictures and running the maps application for an extended period are very costly to the battery life. If you use your phone as a GPS in the car you need to plug it in. If you constantly drain your phone and recharge it you will need a new battery sooner rather than later, because each discharge/recharge is called a charge cycle and the battery only has so many of those before it starts to lose its ability to hold a charge.

Don’t cripple your phone!

The way you use and charge your battery makes as much a difference as the apps draining it. If you charge a totally dead iphone, the battery will fill to 100% charge. If you plug in a partially dead iphone for a short amount of time, it will charge the “uncharged” part of the battery, and will cause damage to the rest. This damage builds up and makes your battery life worse and worse. Long story short, only charge your iphone(or any other device) when the battery is almost dead, and charge it until it is completely full, do not skip the trickle charge phase. If you take care of your battery, it will last MUCH longer. For the skeptics, I will explain the science as lay as I can. It’s really pretty long, but it’s worth reading.

The iPhone uses a Lithium ion battery. It’s a mixed salt battery using a trade secret formula. The advantage of a Li-ion battery as opposed to other rechargeables, like Ni(M)h, is that there is greatly decreased “cell memory.” Think of it like filling a glass with water. If you add 1 cup of water, or a full battery charge, then drink half of that, you now have a half cup. If you add 1/4 cup and drink another half cup, you now have 1/4 cup left. if you add 3/4 cup now, you have a full cup again. This is the ideal scenario, but this isn’t how it works. ALL batteries exhibit memory.

If you charge your phone overnight the first time you use it, you now have a full battery. You basically have a series of towers in your battery. These towers are covered in charged lithium ions. There is also a second set of towers that attract non charged lithium ions. When you apply power via the charger, you are increasing the charge on the ions and they jump from the towers of non charged ions to the towers of charged ions. Conversely, when you use the battery, you are decreasing the charge on the ions and they jump to towers of non charged ions.

Though the goal in a li-ion battery is to make towers that cannot react with the ions, this isn’t possible. When your phone has 20% charge, and you plug it in, a flood of electrons pours over the towers. unfortunately, some of the ions are already charged, and they take on an extra electron. This is a phenomenon that all Electrical Engineers struggle against. These now “over-charged” ions can react with each other to form diatoms, or react with the anode or cathode(the towers) and form completely inert solids. These ions will no longer charge. Now, if you lose 100 ions per charge, your battery will still be within a few percent of it’s original capacity in a year’s time, but if you lose 100,000 per charge, you are treading in dangerous water.

If you plug in your battery, and you have a less than 5 or 10% charge, there is a massive amount of ions that will readily take an electron and the number of already charged ions that will take another minuscule. Whereas if you have a 50% or 75% or 80% charge and you plug it in, there is a very good chance you will over charge a lot of ions.

The iphone has a system in it that evenly spreads the incoming electrons to the towers to make sure there are plenty of uncharged ions to accept charge, but the warmer your battery and environment are, the less effective this is. The battery will try to evenly strip the towers, so when your battery says “80%” charge, though 80% of the capacity has been filled, the battery will take on about double more electrons before all the negative ions will move over. This is why the phone then enters a trickle charge mode. When one electron enters the battery, it will almost never end up over charging an ion, it will be attracted to an uncharged ion and they will pair. Once the towers are fully charged, the ions will accept electrons and they will all move over and the towers themselves will hold a negative(more power) charge.

If you begin allowing your battery to die before recharging it, there is actually a chance that you can reverse some of the damage done. When the battery gets very near to dead, it might begin pulling electrons from the inert reacted ions and allow them to jump to a tower.

If you want your battery to last all day, or two days, or three days, train it to do so. Don’t let it charge for a little extra juice between long charges, don’t pull it at 50% charge, use it for an hour and plug it back in. If you have to unplug it early, let it die before you recharge it. If it is near dead and you have no other option, a few bad cycles won’t be the end of the world, but every time you plug it in when the battery isn’t very low you cause damage.

I have the same phone. Bought just days apart. Only difference is that mine is black and her’s is white.

My phone has all services enabled, but I’m using one thing she’s not….ActiveSync to connect to my corporate email server. I get upwards of 100 emails a day, and all those emails getting pushed to my phone constantly, all day long, has my battery down to less than 20% by 5pm (usually off the charger in the AM around 7:30). My battery can’t make it though a day without having a little booster charge in the car on the way home.

Because of this, I’m thinking push email is the culprit. If I were traveling, and needed to extend battery life, the mail push would be the first thing I’d turn off.

I used to have a Blackberry, and it operated on the EDGE network only. It did have WiFi capability, but I kept it turned off as it would do VoIP over the Wifi and if you walked out of range, you’d loose the call. Very slick feature if you don’t have cell service, but because of that I kept WiFi disabled. My Blackberry battery would drain fairly quickly too, but it would make it to bedtime (usually with only one bar left). The saving grace is that I could bring a spare battery or two if traveling. When the one in the phone died, I popped it out and put in a charged one. Sadly, you have to have an external battery for the iPhone to do anything like that. Apple dropped the ball by not having a removable battery, in my humble opinion.

mine has improved quite a bit in da last few days..follow da instructions 1.RESET NETWORK SETTINGS 2.SWITCH OFF ALL APPLICATIONS LIKE GPS,3G,WIFI,AUTOMATIC TIME UPDATE AND PUSH UNLESS U REQUIRE!!(SAD THOUGH!!) 3.FORCE QUIT EACH ICON INDIVIDUALLU AFTER OPENING DA ICON 4.BRIGHTNESS AT NEXT TO LOW(SWITCH OFF AUTO BRIGHT)

mine has gone 3hrs standby to 16hrs standby wit minimal usage..and 14hrs after moderate usage..its been increasing every other day..its spooky..its got a mind of its own..A.I kinda!!!

pleasr respond if my tips helped u out..cheers!!

frm abu dhabi(uae)

count me in!!!
same issues..hd 2.0 firmware..battery lasted 3hrs on standby..now on da 2.1 version..improved 2 6hrs..standby..wit all functions like 3G,,wifi switched off..believe me..ive switched everythin off..so its jus a plain ****** normal phone wit no battery capacity(id get a better chinese copy of da iphone wit better capacity and functions..no offence 2 any nationalities!!!)..sorry 4 da foul lang..but im really cheezed off!!!

i wanna try da calender sync method..can someone help me wit tht cos i dont seem 2 find tht option in da settings!!how do i change my calender sync setting???

my iphone also kinda heats up like some of u guys!!and my usage counter exaggerates my actual usage,,like say if i used da phone 4 a 5min call..it shows more thn 1 hour of usage..wierd phone!!!

also could any of u advice me if i was to reset network settings..wii my phone get bricked,,as i hv unlocked using turbosim!!

cheers frm dubai,uae

Really? That’s a HUGE battery savings.

But if I *AM* using GPS… why would I want to turn “location services” off (twice? or even once?)

Doesn’t GPS *NEED* “location services”?

We could then go to a new “Settings->Side Switch” and decide for ourselves what we would like that switch do to:

GPS on/off
EDGE on/off
3G on/off
BlueTooth on/off
Ringer on/off
Vibrate on/off
Auto-lock on/off
Wi-Fi on/off

Saving battery-life!

Mine would be configured to:
“Everything off”… but “Wi-FI on”.
(Many airlines are now allowing wi-fi… but you must
turn everything else off.)

… all by instantly, throwing 1 (configured) switch.

1) Turn push mail off. Set mail to fetch at 1 hour intervals.
2) Turn WiFi off when not needed.
3) Turn Bluetooth off when not needed.
4) AND… This one is VITALLY IMPORTANT: when you find yourself using GPS, you MUST go into settings and turn Location Services OFF AGAIN! This is a major bug and hopefully Apple fixes it soon. This 4th step is the one that saved me. It meant the different between having my battery drained before lunch – to having it at at about 90% capacity at bedtime!

Oh, and don’t forget to Digg it UP, people!
(Hit the Digg button at the bottom of the post)

Any iPhone dev’ers on this?? If so, make it… make it free to allow one profile and make a second one for .99 that allows unlimited profiles.

damn i am good

I’ve written up my own list of tips as well:

http://onxo.blogspot.com/2008/07/mobile-tips-to-extend-battery-life.html