Users of the iPhone 5 have discovered enough problems with their new handsets to wonder what they ever saw in the iPhone to begin with. From maps that can't figure out Central America from South Carolina to data leaks that burn up a users data limits within the first week of use.
The data issue is this: the iPhone 5 will use cellular data to get email and other activities even when connected to a WiFi network.
While the issue has gotten attention concerning this behavior on the Verizon network, for some reason very little attention seems to have been paid to the fact that the same thing happens on the AT&T network.
I discovered this issue myself while sending out a text message that contained a picture. The text didn't seem to want to go through despite having a strong WiFi signal. Several attempts failed until I decided to see if it would go through with cell data turned off. That did the trick.
A few minutes later I discovered that in the first week of use I had already burned through more than half my data limit despite not using cellular data for anything other than getting email while away from a WiFi signal.
Verizon users have lucked out, however. They have been issued an update to address the problem. iPhone 5 users who are on the Verizon network need to go into Settings, then General, and then finally About. A message will appear telling the user to wait for an install. Then the user must restart their device.
It is possible that the issue on AT&T is not with the use of cellular data so much as a WiFi issue. If the WiFi signal drops cellular data will take over. All this is done automatically so the user doesn't know they are using data.