More data usage from ATT on the 4s

iCloud?

 

That's what I'm thinking...iCloud. Just found this thread on the AT&T forums that might help explain the usage you're seeing:

http://forums.att.com/t5/MEdia-Net/Wifi-Data-Usage-Question/td-p/1906834

 

Nope.

 

If she is home all of the time have her toggle Cellular data off when she is home. That way any and all data is over WiFi and she can still get SMS and Phone calls. The only draw back is that she wouldn't be able to receive MMS messages from non-IOS users until she toggled it back on.

 

Are you seeing these numbers on the AT&T website, or in Settings - Usage - Cellular Usage? There are reports that the numbers reported on the phone itself are incorrectly reporting some WiFi data as Cellular data, but when you check it at the carrier you'll see that your actual cellular data usage is much lower.

Edit: AT&T's Website (for me anyway) is not displaying data used in my current billing period - only in the prior ones. To check your wife's current usage with AT&T, call *3282# from her phone and AT&T will send her a text message with her "actual" current data usage.

 

So far we have two from AT&T and two from Verizon in my family. It appears through close scrutiny that the data use comparison we've done is pretty equal.