Last week, we asked whether anyone out there in Consumerland had experienced their new iPhones downloading huge amounts of data when the phone wasn’t supposed to be using any data at all. Yes, having a mobile device that uses the faster LTE network means you can use more data faster, but that’s not supposed to happen while you’re connected to wifi. Or driving. Or asleep.

Brian writes that his phone was downloading while he slept:

I have had a similar issue as well. I typically use ~2gb of data and this past cycle since 9/26/12 I’ve used over 4gb. The funny thing was that by 9/26/12 at 7am, while I was asleep I had already used 200mb of data. I also have an unlimited plan with AT&T and will soon be throttled to horrendous speeds.

Louie writes:

After reading the post about the iPhone 5 data gobbling bug affecting AT&T users I decided to check my usage. In 7 days it says I’ve used 1.4 GB of data… thats a period of 10/14-10/21. Last cycle was 9/14/12-10/13/12. In that cycle I used 1.8 gb of data. I had an iphone 4 for one week that cycle and a iphone 5 for three weeks that cycle. So in 3 weeks with an iphone 5 and 1 week with a 4 ,I used 1.8 GB of data, but in one week this cycle with the iphone 5 Ive used almost the same amount? That raised a red flag because I dont feel that my habits this month have been excessive compared to any other time ive used my iphones in the last 6 months.

John writes:

I checked my Cellular usage on my new iPhone 5 which I got the day it was released.

I’ve never hit more than 4gb in a month in the last 2 years and as i look at the screen i see i used
5.6gb since 9/22/12 @ 10:38 – precisely the time my new phone was activated.

I did not use the phone for more cellular than i usually do – and am on WIFI most of the time at home/work.

I did not receive a throttling message from AT&T – YET.

We asked readers who wrote in whether they use any streaming video services on their phones (even while supposedly on wi-fi) that might employ adaptive streaming, adjusting video quality based on what network speeds are available. They insisted that they have not.

Our only advice is to look out for overages, and consider turning off cellular data while you’re on wifi for extended periods, or unconscious.

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