IOS 4.2.1 battery drain

hpgs1807 wrote:
battery life is much worse. maybe 4 hours from 100% to 0 in standby mode. I have the 3G and after some web searching it seems the multitask feature might be the issue, but no fix.

You realize you posted this in the iphone 4 area.

Well, I tried all the tips and tricks to no avail. Since Thanksgiving festivities were all done, I built a fire and restored my iPhone 4 to a "new phone". Took quite a while to reenter all my settings and configs, but I'm not the proud owner of nice, clean iPhone 4. I'll let you all know tomorrow whether that helps with the drain problem.

Hello,

I also did a complete restore and did the "set as new" option. I also did the Battery Calibration and it all seemed to help. My battery was at 100% this morning and its still hanging at 75%. On off web browsing, email, little music (1 hour?) So now I'm happy.

It's a bit extreme but its also a last resort. Might want to consider it.

Finally some progress, i think...

I restored the phone twice (and also once unsuccessfully due to space constraints on the hard disk - iTunes back up can eat space!). Now, the battery drain seems to have eased and gone back to the the pre-4.2 days. This is an early finding, from staring at the battery indicator. I have not checked its validity under usage.

If anyone else have any troubles, try restoring the phone via itunes (after backing up of course) and then resync the contents and apps. Seems to work. I haven't played around with the mail on/off or push settings after that.

I had this very same problem, battery drain. All was ok till I downloaded ios 4.1, umpteen phone calls to Vodafone, my battery drained from 100%-20% in 2 and a bit hours. I upgraded to iphone4, still problem persisted. apple gave me 2 solutions, apps running in background, or restore to factory setting. Once I restored my iphone the problem was gone. Battery life on iphone4 is almost 2 days with moderate to heavy use. Will I download ios 4.2, not yet!

I have restore my iPhone 3GS with the new iOS 4.2.1 and now its seems to be ok.The battery is like it was before, but still the capacity is significantly reduced with the iOS 4. Previous versions of iOS were much better for the iPhone 3GS

I have restore my iPhone 3GS with the new iOS 4.2.1 and now its seems to be ok.The battery is like it was before, but still the capacity is significantly reduced with the iOS 4. Previous versions of iOS were much better for the iPhone 3GS

Interesting. My 3GS has much better battery life on iOS 4.x than it did on 3.1.3. It did not, however, until I disabled multi-player games in Restrictions.

correction..

that didn't work at all. It said 100% in the morning, but once i clicked the home button a couple min after checking it was down to 94%. It appears it was stuck at 100% when it was really not.

Then after last night it drained 70% overnight..

So,,, still broken.

"New Setup" is holding steady this morning. My 4 has been off the charger for about 3.5 hours, has had some light use, and is currently at 99%. Yesterday, after 1 hour with ZERO use, it would drop from 100% to mid-80s. I'm crossing my fingers.

And yes, as an earlier poster had said, one should NOT have to do a "new setup" each time they upgrade. If 4.3 comes out in December, I'm going to hold off until the reports from the field come in. Lesson learned.

I noticed the battery drain issue with the new iOS 4.2.1 as well.
BTW, I have most of the optimized settings implemented:
- Turn off Notification
- Turn off Wifi/3G when not used
- Turn off Fetch New Data in Mail
- etc.
Except:
- My EQ is turned on (since R&B gives much better sound)
- Location service is turned on
Not sure where is the problem.
Nevertheless, I noticed that Location service for Camera is always Active (having small icon next to it in the Setting).
Is it supposed to be like this, even the Camera app is not run?

Also, it seems that Battery indicator on iOS 4.2 is no longer accurate.
You can compare it with those top Battery App, like Battery Doctor.

P.S. What is the "New Setup" referred to please?

"New Setup" means that you do an iPhone restore in iTunes, but rather than restore from a backup, you choose the option to set up as a new iPhone. This will leave your firmware upgrade intact, but remove all your settings, accounts, apps, etc. as if it came right out of the box with the newest firmware. You then have to reconfigure your entire iPhone and reinstall the apps you want. BTW, you will not have to repay for any apps you've purchased, but the associated data will be lost unless it is an app that syncs with the "cloud' or Exchange, etc.

This is a last resort, and I was at that point. It took me about 2 hours last night, but after about 14 hours of "normal" use, my iPhone 4.2.1 is still at around 73%. A couple days ago, I'd be below 10% and that would be with a mid-day recharge.

The "new setup" fixes the issue, but it is a bit of a hassle.

Ughhhhhh I was dreading checking the forums because I was hoping this was just an isolated incident but now I see its a MUCH bigger issue 😟 Directly after updated to 4.2 my battery was at 100% wifi off 3g off woke up just over 6 hours later and it was 33%!?!?!?!

So disappointing! I hope they resolve this!

Be sure to open Safari and close all pages that are open, bring up multi-tasking, kill all apps, power off phone, do two-button full reset holding until Apple logo displays twice and finally powers off and phone remains off after releasing buttons. Power phone up, fully charge, use phone without charging until battery dies. Plug phone in and fully charge overnight. One thing I always try to do is keep all pages in Safari closed and cleaning out the multi-task bar before plugging in to charge at night. There are a couple of small things to do but this should get you on the right track toward maximizing battery life.