Excessive mobile data (cellular data) usage by Documents & Sync

Since the end of February 2016, both my iPad (4th generation) and my iPhone 6 plus have been using excessive amounts of data, mostly with respect to Documents & Sync. For about the last month or so, I've been working with Apple Support to try to find out the cause of the problem. After much troubleshooting on my part (Apple wasn't too helpful), I narrowed the cause down to iCloud services, particularly either iCloud Drive or Notes. During my conversations with an Apple representative, he acknowledged that other users are experiencing a similar problem. This week, I discovered that data usage on my iPad and my iPhone went back to normal levels when my 2012 MacBook Pro (15") running El Capitan was in sleep mode (usually, I leave the MBP in an awake state, but this week deviated from that). Long story short, last night I logged out of iCloud on the MBP and so far data usage on the iPad is zero (I haven't used my iPad at all since last night) and data usage on the iPhone is negligible. I'm going to continue to leave my MBP logged out of iCloud for the rest of the day and check my iPhone's and iPad's data levels this evening. If the data levels continue to remain low, I'll log back into iCloud on the MBP tonight or tomorrow morning and see whether the simple process of logging out and logging back in on the MBP resolves the issue. If not, we'll know that something is corrupt or broken with the iCloud services on my MBP. My current theory is that something on the MBP is causing constant updates to one or more of the iCloud services, which in turn is pushing those updates to my iPhone and iPad, thereby causing the excessive cellular data usage.

I would very much appreciate it if those of you who are seeing excessive cell data usage on your iOS device would please try logging out of iCloud on your MacOS device and seeing whether that stops the cell data usage bleeding on the iOS device and then report back here.

Thanks,

I definitely think I'm onto something with iCloud on the Mac causing the problem with the iOS device to consume data.

At 10:13 p.m. Friday evening (5/20/16), I logged out of iCloud on my MacBook Pro and reset the cell data usage statistics on the iPad. I then went to sleep, leaving my MacBook Pro turned on and awake (but still logged out of iCloud). At 6:32 a.m. Saturday, the iPad was showing absolutely no data usage whatsoever (0 bytes). I continued to leave the MacBook Pro logged out of iCloud but turned on and awake throughout the day yesterday. By 10:18 p.m.—24 hours after logging out of iCloud on the MBP—total cell data use on the iPad was only 13.4MB. Of that amount, 6.2MB was System Services and 2.5MB was Documents & Sync.

At 10:18 p.m. Saturday, I logged back into iCloud on the MBP and left it on (awake) overnight. By 7:34 this morning—less than 12 hours later—data usage on the iPad jumped to 127MB total, 119MB System Services, and 107MB Documents & Sync.

In looking at the iCloud control panel on the MBP, all iCloud services are currently turned on except that Photos only has My Photo Stream and iCloud Photo Sharing turned on; it does not have iCloud Photo Library enabled. The reason is that I have a very large photo library, and when I turned off iCloud services on Friday, the MBP retained the entire Photos library (with all original photos). When I enabled iCloud last night, I received a message that said, “Your full-resolution photos and videos stored n iCloud will not fit on this Mac.” I am going to wait until later to mess with re-syncing the Photos library that is on the cloud with the the library stored locally on my MacBook Pro.

My plan now is to start methodically turning off iCloud services on the MBP one-by-one to see whether I can narrow down the issue to a particular service. At 8:30 a.m. today, I have turned off all iCloud Drive services in the iCloud control panel. When I click the Options button next to iCloud Drive, I see a listing of the following apps that are using iCloud Drive:

• Automator
• Preview
• QuickTime Player
• Script Editor
• TextEdit
• Photos Agent
• iBooks
• iMovie
• Keynote
• Numbers
• Pages
• Mail
• Snapheal

Thus, I’ll be turning off all those items. If data usage goes back to normal, I’ll start turning on those apps/services one-by-one. If data usage does not go back to normal, I’ll next try turning off the Photos services, and then just continue down the line.

Please let me know if any of you are able to reproduce my results by turning off iCloud on an Mac OS device.

I have been having the same issue sort of. I have gone through about 4GB of data in the past 7 days according to my carrier, Verizon, but my usage in the cellular menu only shows 1.4GB for the same period. Contacted apple via chat for assistance and they told me to go to Settings>General>Reset>Reset Network Settings. Did so and will now have to monitor usage via Verizon basically. FYI you will lose any WiFi passwords you have but all the other settings as far as WiFi assist and icloud settings have remained just as they were before. I never had the high amounts of data you spoke of for system services. Hopefully this is a carrier error or the reset will fix the issue.

My details:

iPhone 6s

iOS 9.3.1

except for a few apps I need cellular data is turned off to all the others

After over one month of troubleshooting, I finally discovered the solution for this vexing and annoying problem. As a I suspected, the problem was with one or more files on my MacBook Pro. The solution was to reset the permissions on all the files in my Home folder on the MBP by following these instructions. I strongly recommend that anyone who is experiencing high data usage on an iOS device and who also has a Mac of some type try resetting permissions on the Mac. Please let me know whether this solution works for you.

let me say this - i am no expert here but there is a possible confounding variable that exist on the mobile data plane. my father was so generous enough to allow me on his plan to save some money but stipulated that i must use no more than 2gb. that was fine with me! i thought it was generous; anyways, this past week the bill cycle reset... i have already hit 1.9 GB (according to my dad i have hit 2 according to ATT). why? this STUPID DOCUMENTS AND SYNC.

it has nothing to do with wifi assist. i believe it has everything to do with how much file manipulation you may be doing on your computer and phone when tied to iCloud. example - you annotate a pdf that is 40MB. every time you annotate again and again, it reuploads it...

i hope that makes sense. i'm furious, the first week of getting a gracious gift and i've already abused it (unintentionally). there has got to be a way to turn this crap off. i was NOT EVEN AWARE i used that much data until half way through the week!

HI, I have exactly the same problem. 6gb of data used by documents and sync during a three hour period when I wasn't aware. I went through all the options you did and finally did a reset to a previous backup and deleted my last three new apps. I then didn't have the problem again until this evening where by a data monitor program I had installed informed me that 2gb had been burnt through in 20 min this morning. My usage had not changed.

IM disappointed that I'm not getting any response from Apple other than it must be a setting issue that I'm responsible for. The phone bill is £104 this month. if this continues I will need to change phone

have you got any further?

Hey mate! This sounds like it could be the issue I'm experiencing. This is the only thread I've seen that suggests the Mac could be at fault. How long did it take your Terminal to process the permissions command? Just curious as mine has been processing for a couple of hours now. Cheers!

Im not sure if I would consider 35 mb to be excessive by any stretch of imagination...

I have the same issue, only MUCH worse - my 6S just burned 1 GB (a gig!) within 20 minutes on Documents & Sync. No solution so far, I'm nowrestoring my phone.

Thanks for your post. I'm following your suggestion. Will do some test tomorrow if the data bleeding has stop.

@ russelljsmith - I have the same issue 1.7GB cellular data within short period of time from Documents & Sync on IOS 9.3.1 on iPhone 6 64GB. Very annoying because it eats my battery... 😟 I don't care much about the data usage, but more on battery life...

Dude that would be 5.4gb a day. I am experiencing a whopping 120 to 150 a month gb usage. Even with WiFi on a data off. Yet when you look on the phones stats and add everything up it isn't even close. What I am thinking is everything an iPhone does is converted into a data stream for security,phone calls texts, everything. So basically if you have an iPhone on and not connected to WiFi and actually use it you are using data. That is one expensive *** clock.