Q: IOS 8 High Cellular Data Usage

I contacted Apple Support via chat and the support person had me reset my phone completely. I set it up as a new device and logged into iCloud. I was initially on WiFi for all the setup then turned off WiFi and the Documents & Sync went to 2.5MB within 10 min. The support person said this must be a hardware problem since software problems are fixed by doing a reset, so I have an appointment for the Genius bar for Saturday. Where I don't think it is a hardware problem I think the only way Apple will be able to acknowledge this problem is if enough people actually contact support about it. It might be a pain to restore your device and go through the support process however if all of us actually do so Apple will take the problem more seriously and figure out a fix for it.

Here are the steps I have taken and over 24hrs later it seems to have resolved the massive data drain.

- Complete reset of iPhone 6 Plus

- Log out of iCloud on ALL devices.

- Log in to iCloud on iPhone

- Log in to iCloud on all other devices 1 by 1.

     - I did this step to see if there was one culprit.  Turned out that none of them were and so far so good!

Hope this helps others.  Apple is still looking into my iCloud account but I'm hoping this resolved the issue.

I have switched off most settings (except email & safari) on my wife's phone following the suggestions in this thread.  The only thing connected to the iCloud is Find My Phone.  I have also switched email to manual fetch mode.  However, even though it was connected to wifi, I noticed last night that after 2-3 hours  it still used a few MB of data according to the phone.  The next step is a complete reset but I need to be sure not to loose her contacts.

I had my phone replaced under warranty today at an Apple store set it up as a new device came home disabled all of the usual Data using settings and the issue was still there. I contacted Apple Support again and after 2 hours with them they are finally escalating up to Engineering so I have a call back scheduled. I will update after that.

Also having this problem on an iPad Mini 2 using AT&T cellular data. For me, the mail app has eaten most of the cellular data (far more than it ever has). When I try to get mail, it often appears like it's downloading a lot of email though little will show up in inbox. I suspect it's set up to sync all folders unlike before where opening a folder like junk or trash would then sync new junk or new trash only then. I've tried most of the tips shared in this thread but nothing works. Getting just a few emails today while using cellular data ate about 20MB of data (nothing in them warranting so much data consumption).

I've had to resort to turning off cellular and/or avoiding the use of mail when using cellular (which mostly defeats the purpose of this mobile device for me). Given the variety of iDevices and 4G service providers, the one common thread is iOS 8. My iPad Mini didn't eat 4G data like this before iOS 8. The hardware didn't change.

For the first time ever, I'm about to run into the data limit barely a month after subscribing to the 3-month data plan. Apple needs to fix the problem though I'm sure their cellular service partners appreciate this "bug" very much! My post is on page 9 of this thread. It doesn't appear to be an isolated problem.

Same problem here, iPhone 6 on iOS 8.1.1, used up 1GB of data which is not even the total for all the apps under Settings > Cellular. The total of all the apps and system services should only be a bit under 200 MB yet the total is mysteriously showing over 800 MB of data used.

I had the same problem last Thursday.  I was at working, I got my new Iphone 6 plus over a month. I rarely uses my data, most of the time, I am on WiFi at home or in the office. I first got a message from At&T saying that 75% of my data had been used. 20 minutes later I got a message saying my data had been used 100% and I got 500 MB  more which had usage of 180 MB. I was very busy at work and I turn off data completely.

Later I called ATT and the rep person could not understand how my data had been used, he couldn't give me an answer why this had happen, he said he will give me credit for the overuse. I told him that wouldn't fix the problem, I hang up and I called again and this time I got someone who could help me.

I've called ATT rep, call the Apple rep, and the person from Apple walked me through I had to back up my phone on my computer, with I tunes  and re-install the I-phone and restore the data. So far things seems to be Ok.

But my question still on, and nobody from ATT or Apple could answer me. I do not know if someone was stealing my data usage...Is it possible? Or is it a glitch on the Iphone?

On the outside chance that this has anything to do with it:  would people start including what type of wi-fi security they are using?  i.e. WEP, WPA, WPA2, etc?  I ask because I've seen some serious slowness with my iPhone at home, turns out it may have something to do with our router being set to use WEP, apparently if I switch to WPA or WPA2 that should resolve.  But in the meantime...maybe if things get too slow, the phone is switching to cellular?  Any chance we are all using a WEP wi-fi network?

As for my issue:  I've had my iPhone 6 plus for only 2 weeks and was stunned to click on Settings>Cellular today and see "Cellular Data Usage" set at 9 GB - and I rarely use my phone for anything but texting away from my home network.  (One possibility:  I started an iCloud restore from backup in the Apple store, but it didn't appear to complete until I was at home on my wi-fi network, so I believe it was not trying to download via Cellular.  It was a backup from a pretty full 16 GB iPhone.) 

BUT...the good news is that when I logged into my Verizon account it only shows 200 MB used, all small amounts at 6 hour intervals.   I have received no warnings from Verizon as many others have warning the system is going over, so I'm going to assume the 200 MB value, not 9GB, is correct.  (Settings>Cellular>System Services claims 400 MB used.)   

That said, I don't want to use up even 200 MB of data doing backups every 6 hours unless I know more about how it is being done.  For example, under "Settings-> Cellular Data -> Use Cellular Data For:"  I can see a list of my apps with a data size, typically in MB, underneath.  Is that the size of the App?  with/without the associated data (example:  photos apps plus photos)  or is it just the cellular data usage associated with that app this month? 

I Have had the same problems. I stayed on 8.1.1 for a while, then eventually updated 8.1.2 figuring it would solve the problem, but no it didn't.

SO I was wonderong if it had something to do with icoud drive. I turned off both my iMac, and MacBook pro for 3 days. Now documents & sync only used 4mb of data. As soon as I turned on today, 2 hrs later, I was up to 60.5mb.

so for now, I just shut iCloud drive off all computers and iOS devices, and it seems to work!

DAng, I wish apple would solve this problem, or at least start a reimbursement programs for all the data we have used

This is completely absurd. I was just awakened by a text from AT&T saying that I had used 30% of my monthly data. I had been asleep for 8 hours in my home with a wifi connection. Called Apple support and they had me make a few adjustments, which I doubt will do anything. I've had this phone for one day now, and I'm thinking of returning. This was the fourth time that I had to call Apple support for this phone due to various glitches.

I have wondered if there is a problem with the software on the iPhone that logs the data usage.  I have checked the Vodafone account for my wife's phone for the day the phone said that 200MB of data was suddenly used.  Vodafone is showing that as 2MB!!  In addition my wife's phone seems to have reset the cellular data statistics two nights ago.  I had checked the previous day and the current cumulative usage for the month is now equivalent to maybe two days usage.

estmapper,

The figures you see under settings/cellular for individual applications is the sum of the upload and download data since the last time you reset the statistics on the phone.  The amount of memory the apps take up is under Settings/General/usage/manage storage

You don't need to disable iCloud on everything. In iOS8 go to Settings > iCloud

Turn off Backup. I don't know whether turning off Backup has any significant effect, but I did it as a precaution. I plan to turn it on in the next couple of days before my data plan refreshes just to see what happens.

Then go to Settings > iCloud > iCloud Drive

Scroll down and turn off any apps that you don't need to use iCloud then scroll to the bottom and turn off "Mobile Data"

Then go to Settings > Mobile and from the App list turn off any apps that use streamed media or sync large amounts of data, e.g. Google Drive or which aren't internet dependent such as some games. I've left it on for banking apps, weather, timetables etc.

In iTunes and App Store turn off automatic downloads and/or mobile data. If you have mobile data turned off in the previous stage then it will be automatically disabled so you can - if you want to, I personally don't - enable automatic downloads. Automatic downloads will then only kick in when you are on a WiFi connection.  I only have App store updates enabled because I can't be arsed to keep updating them manually and my storage is only 16Gb so I don't want it shoving every app, iBook or tune that I buy on my computer down the line to my phone and clogging it up.

Finally, go to Settings > General > Background App Refresh and turn that off, or select the more data hungry apps and turn them off. The only apps I was concerned that this might affect were the weather apps but it doesn't seem to have made the slightest bit of difference to their functionality.

Following these measures my data consumption has dropped to 582MB since Dec 5th.

Also when tethering I no longer use Apple mail on my Mac Book Pro.  Apple mail with an IMAP Gmail account uses up to 120MB in a day. Accessing my email on my iPhone or a browser uses a tiny fraction of that.

I should say that I don't know what happens if you leave iCloud enabled on your laptop and you tether it using your phone. i don't think that disabling mobile data for iCloud on your phone will have any effect on data polled by a laptop via a tethered connection. My MBP is still on Mavericks and iCloud drive is only active on my iMac.

Interestingly the problem for me really began when I enabled iCloud Drive on my iMac after the Yosemite beta program reached maturity in October.

I had the problem with EE as well.  It always seemed to happen in the last week of the month.  The data monitor on my EE App would show that I'd used maybe 1.2GB out of a 4GB cap. I'd be feeling flush with only 5 days to go before refresh when suddenly my data would drop to perhaps 300MB available and start dropping by 100 M a day.   If i ran out, EE's first response was to suggest that I move up to a data plan that "better suited my needs" which made me suspect that they were manipulating the data logging of low users to try to bump them up to more expensive plans.

Now the data meter in my EE app is totally blank and all i get is "Request cannot be processed at this time". They finally started to take my complaint seriously when I pointed out that it would probably have been technically impossible for me to have used the 4GB  of data that they claimed I had used in a 48 hour period and threatened them with Ofcom and with terminating my contract unilaterally and forcing them to take me to court for the cancellation fee. Since then they've been pretty compliant with me and even gave me a temporary 12GB cap. But the meter stalled and 5.2GB  and now doesn't give me any info at all...

I'm still not convinced that it's an iPhone problem and not a clandestine scheme being run by EE.

It reminds me very much of the time I found hundreds of short phantom call charges on my home phone bill, to my most frequently called numbers, which clocked up £90 in connection charges which BT couldn't explain. After initially trying to say that "I must have made the calls" and trying to blame my stroke-disabled mother I presented them with verified evidence that the calls could not have been made by anyone at the times listed and they got a senior manager to call and explain that they were waiving the charges as "a gesture of goodwill". When I asked for an explanation of how the charges came to be made and why they were seemingly "hidden" amongst my most frequently called numbers she became very defensive and the only response I was able to elicit amounted to "I'm sorry, I have no explanation" but I was left wondering how many other people had been massively overcharged in this way.

I'm not a conspiracy theorist, but I have no confidence in the honesty of the executives who run the companies nor the people who author their software. In the light of the recent debacle with Amazon's pricing software (and if Amazon can screw up anyone can) I think we can be forgiven for having no confidence in the monitoring software of the major telecoms companies.

I didn't last!  I bought a new 27" iMac this past week (Christmas money and savings) and as soon as I logged into iCloud...boom the drain was back.  To complicate things I then logged out of my old iMac and the data drain stopped.  I've been experimenting and it seems as soon as you add a third laptop/desktop, this problem returns.  To make matters worse Apple, without speaking to me, closed my file and stated the problem as resolved.  Um, no it's not resolved you have a HUGE bug with your implementation of cloud services which basically make your devices useless (need to turn data off on your cell or you need to have one or more computers unsynced).  Kind of defeats the promises of cloud services. 

I recontacted Apple who have now had me run some app on my desktop which collected a large amount of data off my machine (logs, settings) and sent it to them. 

This is beyond frustrating and VERY disappointing give my expectations and support of Apple!

Will continue to update.