IOS 4.2.1 battery drain

******** I BELIEVE SOMETHING IS WRONG WITH 4.2.1 *****************

I have been having this problem ever since I upgraded to 4.2.1. Initially I thought that the device was malfunctioning and I got it replaced through the protection plan. The replacement that I received was by default on 4.2.1. It worked well for few days.Then I played Angry birds. Starting that day It started draining again. I had one hour discussion with Apple tech support arguing that something was wrong with the 4.2.1 update. He advised me that there is nothing as such. If there was Apple Tech support center would be bogged down by complaints. He indicated there might be a corrupt file (out of 4000 songs that I had which did not make any sense), I thought I will listen to him. I restored my device as new phone. It worked well for a month. I did not use Wi-fi or play any games for this month. Yesterday I downloaded iSplash and played for an hour. Now the phone gets overheated and drains out again.

I strongly believe that 4.2.1 is screwing up something and draining out the battery. I can still go for a replacement but I am sure it would be the same with the new device.

I am just waiting for the next version of the OS now.

I could not really understand that compatibility issue with "certain phones of the same model". That's crazy. Though I like the phone, I am seriously disappointed with the restore that I had to do every month or so.

The next version of iOS is unlikely to fix it, because it is not a problem with 4.2.1. Excessive battery drain has been a problem for a few people with every version of iOS since the first. See: http://discussions.apple.com/thread.jspa?messageID=12667836&#12667836

There is an app on the phone that is draining the battery. You need to find out which one it is. Does it happen while you are playing? If so, you know which app it is. But most games drain the battery very quickly. If you continue draining after you have quit the game go to the Recently Used ribbon (while on the Home screen double-press HOME), hold you finger on the game and then tap the "-" to kill it. Also, if the game uses the Game Center that may be your problem. Game Center uses a lot of power.

Hi,

I have a Iphone 4 with OS 4.2.1: Apple has already replaced my battery...
Yesterday evening I charged my battery till 100% for 4 hours.
Then I unplugged and put in airplane mode closing all the applications in background.

How can it be possible that this morning at 6:45 my battery was at 69%????

I really can't understand, any suggestion/help?

thanks

Hello, iebre.

Please go to Settings, General, Usage. Are your Standby and Usage times identical? If so, you may have stumbled across the problem as me: I have an app (NPR news) which will absolutely DESTROY my battery life, even if I close and quit the app! Somehow, it seems to trigger a bug with iOS that prevents it from going to Standby, even if the screen is locked and turned off, and the only solution is to turn the phone off and on again, and stop using that app.

Hope that helps someone...

Hi,

thanks for the hint but it's not my case.
This morning when I checked at 6:45 I had 1 minute usage and 7 hours of standby, while now I have 46 minutes of usage and 12 hours and 12 minutes of standby and the battery percentage is 44%...so it seems that my phone consumes less while using than while in airplane mode

Have you calibrated the battery gauge since the battery was replaced? Charge to 100%, then discharge until the phone turns off and will not turn on. Then charge again for 4 hours. If you still have the problem of the battery going down with no usage showing the new battery is defective.

My brother has been far more patient than I with this issue. He was already on his second iPhone 3GS, with 4.1 installed. Reboots still happened, but not as often, battery drain was still the same (more since updating to 4.x). Then a month ago he started having 3G connection issues. Texts were being received hour or two hours later, sometimes not at all. This is anywhere. Reboot issues started happening more frequently again. We contacted our cellular provider, after an escalation, they found nothing wrong on their end. But decided to reset everything for him, including replacing his SIM card again (third now). But to no avail. Finally contacted Apple Care, and they suggested to "upgrade to 4.2.1 to see IF it helps, if it doesn't we'll swap you out with another phone." He wiped his phone clean and installed a 4.2.1 from scratch. After that reboots slowed down, still happens though. Battery drain was ridiculous. He lost 4% just making 2 texts. Texts issues still persist. So he contacted Apple Care again and got his phone swapped out.

He didn't restore from back up, and he manually put in network settings, and email accounts, as well as his apps. But the same issues that he was dealing with with his previous phone (after updating to 4.2.1) was the same issues he is dealing with with the his third iPhone. I don't know about anyone else, and I can understand that there has always been issues with previous iOS's, but the iOS 4 is by far the worse of the bunch. You'd think that after several versions already, Apple would have worked out the kinks. Not all, but most of them, that these current issues shouldn't be happening. But then again, if they only care about their new devices, and can live with several thousands being unhappy as oppose to many others who aren't, then I guess it's "not an issue". lol

Apple...popularity goes up, quality goes down. I was much happier with them when they were the smart kid brother no one really talked about and sometimes picked on. At least then, they were ALL about quality, not quantity and profit.

I have calibrated the battery many times....almost every evening it goes to 0% but the behaviour was the same even before Apple replaced my battery...

it looks like my phone drains battery more in airplane mode than in standby

Thanks Lawrence. After I quit the game, I did make sure that there were no apps running by closing all of them forcefully. It happens so sporadically that I cannt tag it to a particular application. I think apple should be more careful in what applications they approve of.

Hi Lawrence,

the calibration should impact on the way the software manage the % respect to the effective voltage charge of the battery...
Do you really think that calibration could solve a 35% loss in 7 hours in airplane mode?

Anyway I have tried it several times because my phone does not arrive at the evening and so I reach 0% everyday. The problem is that I already sent my phone to the Apple assistance and they replaced my battery and I remained for 4 days without my phone number (due to the micro sim ). I expect from a serious assistance to find the problem and solve it or at least replace the battery with a very tested one.
I'd not like to send the phone again to the assistance

Yes, the calibration affects it because with Lithium batteries you cannot tell state of charge from voltage, as the voltage is almost constant across almost the full charge cycle. Instead the battery condition circuit assumes that the battery is fully charged after a period of time, and monitors usage to estimate state of charge. It can detect full charge because there is a brief voltage spike when it is reached, and full discharge because the voltage drops suddenly, but in between it estimates.

If you read the thread (I know, it's daunting) you will see that others have reported higher battery drain in Airplane mode than with data enabled. Their solution was to not leave it in airplane mode. The likely reason is that there is an app that doesn't know the phone is in airplane mode and keeps trying (and failing) to communicate. Apps are supposed to give up after 1 timeout, but not all app developers read the manual.

If you have a Push email account there is a failure mode in ActiveSync where it will keep trying to sync over stale connections, and apparently even in Airplane mode. To see if this is the problem (and if you have a Push account) try turning off Push, then reboot the phone (the reboot is essential as Push doesn't change state until after a reboot). If this fixes the problem turn Push back on and reboot again. The problem MAY be fixed at this point.

If it isn't go to Settings/Mail,Contacts,Calendar, tap on the name of the Push account, and turn off the 3 switches. Back out of Settings to the first screen. Then launch Mail, then Contacts, then Calendar to clear pending operations. Reboot the phone, then go back to Settings and turn the switches back on.

Thanks Lawrence but I have already tried, the push account is MobileMe and my problem with airplane mode is with no apps execpt the ones that come with the iOS and with the cellular data disabled (I disabled them just to make the test).

I understand at this point it's clear that there are no suggestions or software to disable to solve such problem...but I really do not like the idea to send the phone again to Apple and remain without my phone number (I use it for my job and it's really a problem)

thanks anyway

Funny, I can recreate the problem:
As posted on Feb 5 I noticed the battery drain issue while I was in London (coming from Germany) and it magically stopped when I returned the same day.
Until yesterday - and guess what: I was again traveling outside of Germany into a different timezone - again to London. This time I carried a charger and had to re-charge the first time 4h after I landed. In the morning it was at 100%, by noon already at 50%, could re-charge on the train a bit, but ended with 10% left when I arrived back in Frankfurt around 21:00.
And as previously reported it healed itself as soon as I arrived in Germany.
I did not re-charge and in the morning it was running at 8%.
So the magic question is:
What is different for the iPhone when one is travelling? Time zone maybe?
I did switch off the automatic time adjust while in London, with no effect and turned it back on prior going onto the plan home.
Ideas?

I'd updated my iPhone to iOS 4.3 and the battery is going to normal again.
The battery was completely charged at 12hours ago, and drained only 4% with Location service enabled and notify enabled.
Realy had anything wrong with iOS 4.2.1

The iPhone is in 13hours in stand-by and 17min in use.