iOS 8 battery drain - Calendar, Contacts, Notes

I'm experiencing the same problem with battery life. My usage profile is different but, like you, I'm down to about 4 hours before needing a charge. I have made no other changes to my phone since upgrading from IOS 7.

I don't seem to have any other issues with IOS 8 yet and have not seen a similar battery degradation on my iPad (3rd generation).

Jason

iP4S, Calendar eating up battery more than any other app.. Closing it from task managed did not help..

Same problem. Phone is warm, contacts and calendar taking the majority of the battery. Closing those apps doesn't make a difference.

Have you tried to re-calibrate the battery? Let the battery go down to 0% then let it charge back to 100% without unplugging power cable.

Yes because that's what happens when the battery drains. It eventually goes to zero percent, so I'll plug it in and get it to 100%. I have the brand new battery from the iPhone 5 recall too that is less than 2 or 3 weeks old.

Same here, my iPhone get Hot and the battery drains really fast when i'm using it! Already tried to recover ten times, to set as a new iPhone and restore backup, already tried everything and nothing seems to solve! My iPhone drains about 1% every minute/ two... It's strange because when it's at Stand By Mode it seems to be normal.... Really don't know what to do... I have an iPhone 5S 64GB. iOS 8.0.2 didn't help at all

have you tried turning off background app refresh? have that completely turned off on my iphone.

but perhaps more specifically you could try changing the push specifically to manual for the apple icloud stuff (calendar, mail, etc.).

this is how it looks on my iphone 5 with ios 8.0.2:

settings > mail contacts calendars > fetch new data > apple icloud > manual

also have other specific items set to manual. so only specific service updates when you are only in mail app, calendar app, contacts app, notes app, etc.

but keep the top push button on (green) for other apps that require push (and hopefully are better behaved).

maybe your iphone is stuck always updating your mail, calendar, contacts, etc. ???

Same issue here. iPhone 5 was fine with ios7, but when I upgraded to ios 8 my phone gets warm and battery drains rapidly (3-4 hours) with very limited use. Checked my battery usage this morning (last 24 hours) and Calendar used 82%. I have tried everything....not sure what to do. My iphone has become a paper weight on my desk because it is constantly needing a charge.

It dropped 2% while typing this post!

Same with my 4S after upgrading to 8 / 8.02 - see my post Background action draining my battery..

Do you have these bug log entries as well? (in diagnostic + usage data)

Same problem. Tried to factory-reset my iPhone and restore data (and configurations) from backup I made, no change. The calendar still drained the battery like crazy. So I did factory reset WITHOUT restoring my data (nor configurations). I had to configure my mailboxes and calendar syncing manually, but the battery problem is gone now.

I finally fixed it.

- Delete the mail/calendar/contacts account you think might be problematic (or maybe all of them. I assumed it was my work account).

- Reboot the phone.

- Set up new account(s) that you previously deleted.

Since doing that, I don't have the battery drain anymore.

I did the above thing and also suspected it was my work Exchange account. Deleting the account fixed it and it's now re-added and doesn't seem to be causing a battery drain with background activity.

these two days my iPhone got the same issue...the notes consumed 23% power at "background activity" ......

Had exactly identical problem: iphone feels warm at all times and showing notes and calendars running in the background. All this resulted in battery draining 80% to 0 in 6-8 hours. I disabled Push, Background app refresh and so on, nothing helped. I did fresh DFU restore with iCloud data restoration- sadly, same thing. I battled this for a while and the only thing that resolved the problem was clean DFU restore with fresh apps installation, NO ICLOUD RESTORE this time. My iPhone 6 plus lasts 2 days easy now and runs way smoother/faster. Pretty sad I had to kiss my backup goodbye. I simply wrote all the settings and the apps I use and decided to not use iCloud any more.

I had the same issue with Contacts, Calendar and Notes using battery life. I seemed to found that issue by going to cellular and disabling cellular use for those items. Now they can use data and run in the background. there is a bug in the software and this seemed to help.