Apple rolled out a third beta of iOS 6 to developers on Monday that included a number of bug fixes, adjustments, and new features for the iPhone, iPad, and iPod Touch operating system. Buried in one of the settings pages was one unsettling change: It appears AT&T is prepared to charge its customers extra to use FaceTime over 3G.

Eagle-eyed beta testers over at 9to5mac noticed a new screen when attempting to test FaceBook over 3G with their iPhones running iOS 6 beta 3. They were blocked by a pop-up message from AT&T that directed them to contact AT&T in order to enable FaceTime over 3G on their accounts. AT&T uses a similar pop-up message to head off iPhone owners attempting to set up the mobile hotspot feature, which requires an extra $20 monthly fee to be used.

Interestingly, when the 9to5mac team attempted to replicate the warning message results using a Verizon Wireless iPhone, they were not met with the same screen directing them to contact Verizon in order to use FaceTime over 3G.

[ For a sneak peek at the next iPhone display technology, see iPhone 5 Display To Use In-Cell Tech. ]

AT&T, responding to queries from 9to5mac about their finding, said in a statement, "We're working closely with Apple on the new developer build of iOS6 and we'll share more information with our customers as it becomes available."

That means AT&T will probably remain mum on the subject until Apple launches iOS 6 to all iOS device users later this year.

FaceTime was launched with iOS 4 on the iPhone 4 in June 2010. Since launch, it has only worked via Wi-Fi wireless connections and not via cellular wireless connections. In other words, iPhone and iPad users looking to spend some quality face-to-face time with one another have to find a Wi-Fi network first. Wi-Fi networks are of course hyper local, whereas cellular data networks are far more ubiquitous.

That changed in June when Apple announced iOS 6 at its Worldwide Developer Conference. One of iOS 6's many new features is support for conducting FaceTime over 3G/4G cellular data networks in addition to Wi-Fi.

FaceTime over Wi-Fi has always been free. That is likely to remain unchanged, but AT&T might not allow its iPhone customers to hog up its cellular bandwidth without paying extra for it. The question is, how much extra? AT&T used to offer a Video Share service that was appallingly expensive. Users had to pay a varying monthly fee in addition to per-minute charges of $0.25.

My guess is AT&T won't go by the per-minute rate, but will instead ask customers to pay an extra $5 or $10 per month in order to use FaceTime over 3G/4G.

Will you pay for this feature, or do you even use FaceTime over Wi-Fi?

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