Q: The iPhone 5 uses Cellular Data over WiFi?

Why would you return the phone? Apple eventually will fix the issue, but in the mean time, you have a work around when on wifi. Just monitor your usage in the mean time.

you're doing better than me, mine's on ATT, but I've only had my iPhone cinco since midday on the 26th and mine shows to have consumed over 3.5Gb of data. No videos watched, all the apps were downloaded while on wifi, a little twitter usage and some facebook and that's all. Glad I'm still on an unlimited data plan!

Has anyone cracked this mystery yet?  I'm running into the exact same problem and now have to upgrade my data plan to keep from having overages.  It looks like iTunes music downloads that were started over wifi continued over cellular, even though "Use Cellular" for iTunes was turned off.

Message was edited by: JordanOVT.  Added more information.

See my previous post.

On page 2...

On any iPhone WiFi is turned off when the phone is asleep (when the screen is off), so any background apps will use cellular data, unless the phone is plugged in to power.

Yes same thing is happening to me! On Tuesday night I got a text from AT&T saying that I had used up 65% of my data after 7 days of my new billing cycle when i usually only use about 1.5 gb a month. I called and the AT&T worker told me that was wrong and I still had 88% of my data free left to use with only .4 of a gb used.

Last night just trolling around and decided to check my data usuage and it is up to 2.1 gb in 2 days! I called AT&T right away and with no questions asked the lady gave me a $30 dollar credit for this month just in case I go over since I'm already up to 2.1 gb in 10 days and every gb over is $10 -__-

hopefully this is fixed soon. Whenever I'm on wifi i turn off the cellular data and it looks like its fine now. Hopefully this is fixed soon!!

Oh and yes I am using an iPhone 5

Spent an hour and a half with a Verizon technical support guy today who acknowledged there was an issue at Verizon but also agreed that my phone is indeed using more data. My husband's, with the SAME configuration, used about 400KB all day according to the phone's usage log. I had mine on for about 20 minutes and it logged 6MB. He said shared data is being either sent to or received by Verizon incorrectly and VZ knows it. So if AT&T is having the same problem, the issue is with the phone? He wants me to do a factory reset. I read others who said that will do nothing. I will though.

As to why I would return the phone? Because I can with no penalty but the activation fee. We also get really lousy reception in our home and have no land line. One bar and calls going right to voicemail. Might look at a wifi signal booster. I am also new to VZ so I don't know how much of this is the tower location. We are supposed to be in the middle of 4G land.

I like the phone, it's nice and everything, but it's my connection to my clients. I've gone several years being constantly connected to my clients, they love me because they email me and I return their messages immediately.  Not being able to push means that's not happening. Bad for business and blaming it on my phone isn't my style. My last phone might not have been real sexy but it was a workhorse.

I look after my mom and spend a lot of time in hospitals and at her house, that's why I do a lot of work on the road. Besides that, if I can't see Facebook photos of what my friends are eating for lunch, i just feel empty inside.

I ordered my iPhone 5 last week but I'm thinking of canceling the order and re-order it once this problem gets fixed. I would ONLY have 2GB and I don't want them to charge me for my data that I'm NOT using.

I'm thinking of canceling my order tomorrow because of these issue..should I?

Why would you? It's a non issue if you turn off Cellular Data while on wifi. It's a great phone and the issue wil get resolved.

On my iPhone 4, right now I have unlimited but if I get a new phone, Verizon told me they going to replace my unlimited data to 2GB. Would it still be worth it?

give this a try...

turn off the thing that reports diagnostic usage

also turn off ad tracking, and all push notifications and things like that... anything that will run in the background off data

i always turn all that off anyways, i used about a gig this week but thats normal for me, when im at work i constantly stream radio and use my phone... so i havent noticed any weird data usage.

How do you turn off Ad Tracking? Where do we go?

I think it's still worth it. I don't know how everyone else uses this much data, I'm a small 608mb since the change.