IOS 4.2.1 battery drain

What worked for me also was plugging iPhone 4 into Itunes, backing up and after that pressing the restore button. I just restored from previous backup (and did not set up my iPhone as a new phone).

Before that my phone was draining battery like mad.

Other things i do is:

1. Fetch mail every 30min (instead of push)
2. Kill all unnecessary background apps
3. Turn of wifi when I leave home
4. Keep brightness at 40%

I do keep notifications, location services and 3G on at all times, only Bluetooth is disabled.

Now I do get satisfactory battery life. I would say 7-9 hours of usage and 36 hours of Standby. I am fairly satisfied with this battery life.

Hi,

Last night I updated to 4.2.1 the battery had been at 100%. This morning it dropped to 73% (I have an app that runs overnight so the drain is not bad.) this morning it was at 73%, and now I'm sittig a 54%.

I'm kind of feeling like I get better battery life... Either that or it's wishul thinking. What about you?

My battery life has dropped significantly with the new iOS 😟

My battery is much better with this update.

Now I am at 6 hours 15 minutes usage and 1 day and 9 hours stand by and still have 12%. Where with 4.1 I get only 4 hours and 30 minutes and one day of stand by.

Debbeh

Got rock hard numbers, cool.

I do feel like I'm gettin more out of the battery. I will post the amount in the morning to help decide.

For me it is slightly better compared to iOS4.1.

Seemed slightly worse right after update, but it seems better than iOS 4.1 now.

First day after upgrade, I have for the first time experienced, that the iPhone didn't last a day fra 8 am (fully charged) til 10 pm with moderate use.

Further I experiended also for the first time, that I lost signal and bluetooth headset connection problems got even worse.

I am definitely NOT happy about this upgrade.

rgds,
Claus

Looks like I have the same drainage issues as with ios 4.1. 100% at bedtime last night, 60% this morning. Very disappointing.

Hi seems to be after 4.2.1 Battery life is better.

my usage 2 hours and 53 Minutes - current Batter % remaining - 56%
Standby - 17 hours and 29 Minutes.

After IOS upgrade - Please turn off the IPhone and ON again.

Try to Follow apples instruction that will help improve your battery performance.
here is the link

www.apple.com/batteries/iphone.html

It seems that my battery drains much faster now! :((

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.

My battery drains much faster... It's 2-3 percent every 5-10 minutes. Full restore didn't fix it.

Same here. After an overnight charge, within an hour of non-use on standby with no applications running, no setting differences from 4.1, and no "findmyiphone", my previously perfect iPhone 4 went from 100% to 83%...1 friggin' hour.