High iOS 6 Data Usage? Turn off iCloud,

I did some investigation with a data sniffer and it seems that the problem is with the validation check of Google's certificates in secure connections (SSL/TLS).

So the workaround is to disable any GMail accounts and remove any Google Calendars.

The problem may also apply to other secure connections with certificates from Thawte.

I submited my findings to Apple...

That's strange.

I deleted my iCloud account and set up Google calendars, mail & contacts on iPhone.

3G data usage has been fine since, with no constant 1-2KB/s drain.

Whoa, spoke too soon.

Instead of constant 1-2KB/s, I now get 500KB over 0.5 hours, with no apps running.

I'll try re-instating iCloud & remove all Google accounts.

I installed Onavo from iTunes store (free app). They are so overwhelmed with demand that it took four days for the product to provide any data about usage at all. So there is a big lag and maybe if it has sufficient capacity I will be able to track my use properly this week. On a very small data set two thirds of the mobile data is Apple Services but not sure what they are. Nothing on Gmail unless its use is masked as an Apple Service because I access gmail via Apple's mail client.

MeLis have you a view on that?

What I am trying to do is to find the service(s) that are grabbing the data and from there I can make some progress.

Once I have a week's data, I will try removing gmail and see what that does.

The nature of this problem - it requires a bit of moving around locations to replicate the fault so it takes some days to assess anything you do.

I've tried it but It seems that Onavo can't catch iOS internals...

The only reliable way examine this is to close cellurar data, and let a sniffer to grab all the traffic through wi-fi. You don't need more than a couple of hours...

del

Yes I am going to delete Onavo because it just does not catch the vast majority of the data nor provide me enough granular detail: I get two big buckets - Apple services and "one other apps lightly" that other app represents by far the second largest data use. The total data captured is about 10% of my use as measured by other tools.

I am not sure what a sniffer is; can one download it easily? I would not be willing to jailbreak my phone so it would need to be an apple sanctioned app.

But your analysis is that it is gmail doing this ???

Thanks for your comments very helpful

I spoke to an Apple Genius in Glasgow today, who hadn't heard of this problem!

He then referred the case to iTunes, who emailed me within a few hours to tell me the following:

"Your request for assistance has reached iTunes Store Customer Support, which answers questions about billing, customer accounts, downloading purchases, and iTunes Store content.

For this issue, you may get advice, insight, and hands-on technical support at a local Apple Store (there may be a fee for the visit). Find the Apple Store nearest you and click the link to make a reservation at the Genius Bar."

Is this problem only limited to certain 3G networks? I am on EE (formerly Orange) UK.

I am using a prepaid account with Three in Hong Kong. I have had the same problem since upgrading to iOS 6. However, here is an interesting observation...

The data 'leak' seems to go beyond what is reported in the Cellular Network Data statistics in the Settings app. The amount I am charged each day implies that I am downloading humongous amounts of data a day although the Cellular Network Data stats show only about 1MB (which is a figure that is pretty normal average figure for my usage level in past few years). So the data that is used is not even being recorded by the iOS cellular data monitoring routines.

This would explain why many users don't believe they are affected. They are only looking at the stats in for Cellular Network Data. And unless they have some data caps in place or are paying based on amount of data used, they would never suspect something was not normal.

There are several different problems discussed in this thread. You mention one of them that tends to get lost; if the usage counter on your phone does not agree with what you are being charged by your carrier there is a problem in the carrier's recording system. The two sources of data should agree to within a few percent.

Data leakage is a separate issue. There will always be some; some of the built in apps can only get data via cellular, because it is routed by Apple through the carrier's network. The most obvious example of this is visual voicemail. There's also some types of notifications. But this leakage is small. It should be around 1-2k per hour, except for VVM messages, which are audio recordings that are sent directly from the carrier's servers, and thus can only go over their network.

Cellular data usage while you are actively using WiFi should not happen, except for the special case I just mentioned. If it does there is something wrong with your phone or iOS, and early reports are that 6.0.1 fixes this specific issue.

Cellular usage while the phone is asleep and not plugged in to power is normal and the way the phone was designed to work for background apps, as the phone turns off WiFi when asleep. All versions of iOS have worked this way; it's to prevent the battery from going flat while on standby because WiFi when on uses power continuously, whether data are being transferred or not.

Cellular usage while the phone is asleep and plugged in should not happen, except for the "background" usage I mentioned in the 2nd paragraph. But the only way you can know is to use a tracking app that records time-stamped usage on the phone, or by noting the usage before and after each period of standby from Settings/General/Usage.

Finally, for most carriers, you cannot tell from their web site or bill when data transfers actually happened. The time stamp on reported data transfers is the time cumulative usage was posted to their billing system, and can represent data that accrued over a long period of time, up to 24 hours. So, except for the total, usage reported by your carrier is useless for diagnosis.

All of these factors tend to get lumped together in this discussion; it would be helpful when posting if you describe which scenario is causing your issue.

There will always be a discrepancy between what the phone reports and what the service provider deducts from your plan. Some data, such as texts and MMS images, show up on the phone as data, but are not deducted as such from your data plan, but they do use the cellular data stream. Don't quote me on that, though.

With respect to visual voicemail as being a stealth data user, that is probably true, but this assumes that one gets many voicemails. I hardly ever do, whether on wifi or not. And certainly not when I am seeing data drain on my phone.

I am still having cell data being used while on wifi. It still averages about 1-2 MBs per day, but because I can't square up what DataWiz tells me to what AT&T deducts from my plan, I will never really know how much or what app is responsible.

This underscores the importance of being able to track data usage by app. Onavo apparently lumps much into Apple Systems usage, so that's not very helpful. Don't quote me on that either.

AT&T should at least offer a more detailed data usage chart for those who want or need to pin down problem areas.

Stan, the packet analyzer can be installed only on a computer. You almost see the raw data on the network. To use it, you must have knowledge of TCP/IP stack etc...

The combination of google's certificates and iOS 6's certificate validation mechanism cause the problem.

Tom, this problem doesn't has to do with providers but with iOS 6 and the certificates. (Certificates are used in secure connections, e.g. when you connect to an https... site, and other services).

Sorry to be a bit thick meLiS.

Are Google's certificates operating when using iCloud, even though I've deleted all Google accounts on my phone?

iCloud? No they are different services. You must use GMail, Google Calendars and other services from Google through secure connections. And as I'm reading now, the search from Safari is also using a secure connection with google.

OK. But this doesn't explain the data usage when only using iCloud.