What ate my data?

July 17, 2015 1:36 AM

According to my carrier, my iphone 5S had two registered data usages at 12:00am on the 15th for a total of 575MB. The problem is, I was asleep at the time, and the phone should have been accessing our wireless connection. So what ate the last of my data?

I'm assuming that there was some sort of automatic software update at that time, but the phone is set to use our WiFi if it's in range (it was) and available (it was - no downtime). I had updated my apps via the AppStore a day or two prior (set to use WiFi only), and as far as I can tell, that was done without any problems.

Is there any way of figuring out what caused this? I've gone into Settings/Mobile and scrolled down the list to see what's using data. Most of the apps are set to WiFi and the few that aren't don't list huge amounts of data used.

Can anyone shed some light on what happened?

posted by ninazer0 to Computers & Internet (11 answers total)

Response by poster: I should probably point out that I'm in Australia and my plan is with Telstra.
posted by ninazer0 at 1:36 AM on July 17, 2015

Go to Settings->Cellular and then scroll down. You should see a total usage figure, and figures per-app below that. Tap on "System Services" at the bottom to see the built-in stuff broken down.
posted by pompomtom at 1:46 AM on July 17, 2015

(though that won't give you specifics on time, so it'd help if you've reset the stats recently)
posted by pompomtom at 1:48 AM on July 17, 2015

Response by poster: I've done that - nothing in System services is close to 575MB. The only thing that looks a little high is Twitter, but that's showing just over 1G of data used (since I bought the phone a year and a half ago)(and no, I haven't reset it recently). I don't use Twitter that often, but it just sits there and ticks over and I glance at it from time to time.

Could it be a carrier error?
posted by ninazer0 at 2:02 AM on July 17, 2015

Given the time of day is midnight, it makes me suspect this is Telstra's billing/usage systems doing a roll-up tally of data consumed for the preceding day (or week, etc) as the clock ticks over to the next. I'm not sure whether this is reflected in your previous bills though?

It may be worth a call to Telstra, although I'd worry you'll get not much more than a scripted answer. You might be able to bolster your case with the iPhones data usage stats.
posted by sektah at 2:42 AM on July 17, 2015

Does your router have automatic healing, or whatever it's called? The thing where it reboots itself at a set time?

If so, it might be that your phone was downloading an update whilst the router was unavailable.
posted by veedubya at 3:14 AM on July 17, 2015

If you decide to query or contest the charges here's a tip a Telstra person told me: if you don't get a resolution on your first phone call, go straight to Complaints on your next. 'Complaints' provide you with a dedicated customer service person, with their own phone number, and the power to correct any errors.

(I once received an $800 data charge for my Telstra satellite internet. It worried me a lot. I went back and forth, back and forth with no resolution. Then the next bill came for $22,000. All I could do was laugh, ring them again and gleefully cry 'Complaints!'. That's when I learned the tip about complaints and my erroneous $22k bill was eradicated quickly with much apologies.)
posted by Thella at 4:18 AM on July 17, 2015 [5 favorites]

Are you backing up your iPhone to iCloud? That sounds about the right size of a backup.
posted by youknowwhatpart at 5:38 AM on July 17, 2015 [1 favorite]

This happened to me.

I had, earlier in the evening, downloaded the latest update to the iOS. I don't remember what version of it, but I think it was one or the bigger ones, 6.X to 7.0 maybe. I was at home on my wifi. The download/update completed normally, and I went about my evening, plugged my phone in to charge and went to bed. The next morning I got a notification that I had gone over my 10gb data plan by almost 2gb. I was already close on my data that month, so I had been monitoring it pretty carefully.

When I called AT&T, the rep informed me that the iOS update could install itself, tell you it was finished, and then still need to download/install extra pieces of the update that could be done in the background.

The important part - she also informed me that when your phone is in sleep mode (not turned off, just asleep), after a certain timeframe, it would disconnect from your wifi, *whether you wanted it to or not*. So my phone downloaded all the additional update stuff without actually using the wifi I wanted it to use. Apparently this functionality is a design decision made by Apple, and the carrier has no control over it. She credited me 2gb of extra data without any hassle.
posted by markslack at 7:04 AM on July 17, 2015 [2 favorites]

I would count on carrier error. While yes, the phone disconnects from wifi while sleeping (to save battery), if it needs to do a backup it reconnects to the wifi. iCloud backups only run over wifi. The only thing I can think of would be if you have automatic app updates set to allow over cellular. You can check this under Setting>iTunes and App Store and check the toggles for updates and use cellular data. But even then, that sounds like a lot of data for just updating apps. (Fwiw, I've never heard of additional components requiring download after a full iOS update. Not sure where ATT got that from. They may have been referring to app updates, which if you were doing a major upgrade, there may have been lots to run due to compatibility issues.)
posted by bluloo at 10:05 AM on July 17, 2015

I assume that it would be the same for system updates, but iOS limits cellular app updates to 100MB, so it seems unlikely that it would download so much data for any kind of update without doing it over WiFi.
posted by homesickness at 10:24 AM on July 17, 2015