IOS 4.2.1 battery drain

Yes! Since upgrading to IOS 4.2.1, my iPhone lasts less than 5 hours on a full charge -- even if it sits idle. Oh... and it runs warm-to-hot which suggests to me there's some serious data transfer going on.

Please read the thread you posted to for advice on how to fix it.

I am having the exact same issue. Phantom usage connected to the exchange email account (only account on the phone). I am using Exchange 2010 as well.

Message was edited by: gurt_l

Read the thread you posted to for solutions.

Try a restore as new iPhone when connected to iTunes. It worked for me.

I am happy to report that since doing this my battery life has skyrocketed. Today I have almost 20 hours stand by time and almost 9 hours usage time and I am at 14%. That's a ton of geocaching while listening to music, a 1 hour phone call, twitter, FB, pictures galore, editing galore, and a 5 minute video.

This is sooooo much better than my iPhone 3G.

Again do restore as a new iPhone. It works.

Yeah, but you know what? I don't want to set the phone up as new every time I have my phone updated to a newer, "better" OS.

I've already lost 2 years of SMS and game data when I set up my iPhone 4 as new after some slighty bigger battery drain issues (10 - 15% per hour of being idle) and would hate to lose the last 5 months of data that I've accrued since the restart thanks to an unknown issue.

Deleting and re-adding all of the push accounts, leaving out the mobileme find my iphone function, resetting the network settings and then resetting all of the phone's other settings have not lead an increase in battery life since updating to 4.2.

I don't want to start from scratch again

I just wanted to add. I was having issues with my battery as well. I read the whole thread on Sunday and followed the recommended steps that Lawrence had posted that may resolve the issues. I charged my iPhone 4 to 100 percent Sunday, used my phone as normal phone calls, checking emails, etc..and as of this morning 8:50am CT my battery life s at 27%, 7 hrs usage, and 1 day 13 hours standby as listed on my phone. I did a reset of the stats at 4:30pm on Sun. I can say before looking for solutions my battery would drain in less that 4 hrs. I can also say I had many apps still running in the background that may have contributed to the drainage. I now turn off the mail, location, bluetooth, wifi and 3G, yahoo, pandora, and others that I use the most. Thank you to everyone who has contributed their issues, suggestions, and possible solutions. It has help me better understand my phone and usage.

**edit to add** I did not have to restore my phone as new. I reset the Network and turned off the emails as stated in the steps to resolve.

Sheila J.

Message was edited by: Sheila J.

I would like to confirm for you that i sync with exchange 2010 and had battery drain issues since 4.2.1. I tried resetting my settings, turning off all services (location, BT, wifi, push mail, etc) and would still get battery drain. I noticed under time since last full charge my usage and standby times were identical.

After some googling I did find where someone had a rogue exchange account causing battery drain in an earlier ios version. So I deleted the account from the phone restarted it, added the account back and charged the phone. Seems ok now.

WIFI on, Location and notifications enabled, and also push.
Usage 1h 57 min, Standby 9h 30min 87% battery left

I havent had the time to go through all the replies, but it seems that there is some of the apps you have on your phone that is still draining the battery. The only suggestion that I could tell you to try is to remove most of apps and then reinstall and do a time check after you reboot and run every one. A quicker way would be to see in the multitask scroll area if the app restarts itself after you quit it out.

Jason

you are correct, looks like battery issue #2 is some app notifications, I had turned it back on this morning from having it off over the last 5 days. I felt it was safe to turn it back on since redoing the exchange account the other night fixed the battery usage statistics. I charged the battery back up and my usage and standby were identical again. Turning off notifications seems to have calmed it down again. Now I get to have fun finding the new culprit.

I'm not sure if my battery is draining quicker, or the phone is more accurate in reporting the battery charge level.

Before 4.2.1 update, my battery would say 100% even after a couple of phone calls and pulling up an app or two (like Weather Channel) and would be kind of like the gas gage on some cars - the first half goes by slowly, but the 2nd half flies by...

Now, it seems to indicate the charge dropping from soon after I use the phone the first time after unplugging.

Overall, I don't believe the battery life is any shorter... and in fact, might actually be a bit longer (then again, I am better at actually closing apps out of the multi-tasking bar than I use to be...).

Yes, I have found the 'battery issue' as well after the 4.x upgrade. I was blaming it on an app I just bought, but it's actually this multitasking feature.

It is definetly due to apps remaing open in the background even if you don't 'multitask' them. Also, these apps remained running in the background even after a reset or power cycle.

To stop the background apps, just follow these instructions....

double tap the home button to see the current background tasks.
press and hold one of the task until the icons shake with a small red minus sign in the upper left hand corner. Keep hitting all the minus signs until all the background apps are stopped or 'killed'. I found many (>50) still running...

Once all the background apps are stopped the battery will no longer drain rapidly.

On a more technical note....
If you have notifications on... there are apps that will actually 'start' by themselves in the background. If all apps are silent (not busy) the CPU should go into a sleep mode to conserve battery life and keep the phone cool. If an app gets stuck for whatever reason like accessing the web the CPU will continue at full speed causing the phone to get warm.

To see apps starting by themselves, kill them all and then wait a couple minutes. Check for background apps again by double hitting the home button. Apps like Facebook will be active even though you never 'started' them.

This solution will get your battery life back. I thought I was going to have to dig my 2G out of the drawer to get my 3GS in for service.....

If you actually read the thread to which you posted you will see that much of what you wrote is untrue. And what you wrote is also a repeat. Users have closed all apps in the quick-start bar and their battery drain continues. And others have solved the battery drain without closing apps.

Sheila J. wrote:
I just wanted to add. I was having issues with my battery as well. I read the whole thread on Sunday and followed the recommended steps that Lawrence had posted that may resolve the issues. I charged my iPhone 4 to 100 percent Sunday, used my phone as normal phone calls, checking emails, etc..and as of this morning 8:50am CT my battery life s at 27%, 7 hrs usage, and 1 day 13 hours standby as listed on my phone. I did a reset of the stats at 4:30pm on Sun. I can say before looking for solutions my battery would drain in less that 4 hrs. I can also say I had many apps still running in the background that may have contributed to the drainage. I now turn off the mail, location, bluetooth, wifi and 3G, yahoo, pandora, and others that I use the most. Thank you to everyone who has contributed their issues, suggestions, and possible solutions. It has help me better understand my phone and usage.

**edit to add** I did not have to restore my phone as new. I reset the Network and turned off the emails as stated in the steps to resolve.

Sheila J.

Message was edited by: Sheila J.

The one main beef I have, is that people are doing things to get their phones in some working order, that they never had to before. It's one thing about resetting network, Mail, and even restoring your phone as new. But when you consistently have to turn off wi-fi, bluetooth, and making a habit of doing the multiple step of turning off apps, just so your phone works relatively as well as it did prior to the update, there is definitely something wrong. Up until now, I've NEVER owned an Apple product that "just DIDN'T work" as it should.

However, my new iP4 is working great under 4.1. No issues like I had in my previous 3GS's running 4.0-4.1.2, and no issues others are having after upgrading to 4.2.1. I think I'll leave my phone alone this time around. Air-print and extra ring tones aren't enough (or worth it) for me to possible go through the same crap I did the last 4 months after upgrading to 4.0.

Eric Shawn2 wrote:
The one main beef I have, is that people are doing things to get their phones in some working order, that they never had to before. It's one thing about resetting network, Mail, and even restoring your phone as new. But when you consistently have to turn off wi-fi, bluetooth, and making a habit of doing the multiple step of turning off apps, just so your phone works relatively as well as it did prior to the update, there is definitely something wrong. Up until now, I've NEVER owned an Apple product that "just DIDN'T work" as it should.

You shouldn't have to turn off wifi or anything else. What you need to do is fix what's broken. Then you can keep everything on and it will just work. The update process sometimes breaks things for a few people. It shouldn't but it does. It has happened with every version since the first update in September 2007. It is not something unique to 4.2.1. Maybe Apple figures its easier to fix it individually for the few people it affects rather than find the root cause. Or maybe there are so many root causes that there is no one fix. If you read the thread all the way through you will see that there are a lot of different things to try, and that different solutions work for different people. The conclusion must be that it is not one problem, but many, and each one only affects a few users. Even collectively it isn't a large problem in the 100 million iPhone world. Unless you are the one to have it.

If all else fails it can infallibly be cured by erasing all content and settings, then restoring as a new phone. Which is unacceptable to some users (a view I have sympathy with), even though some of those users think nothing of reformatting their Windows system periodically to fix intractable problems.