Entner said there is not any technology reason for AT&T to restrict Wi-Fi calling to the U.S., Puerto Rico and the Virgin Islands. For business travelers trying to lower costs when abroad, calls made on Wi-Fi can sidestep international calling rates of 20 cents to $1 a minute, he said.
"Again, maybe AT&T is being careful on [geographic coverage] for a legal reason," he said.
AT&T said the iPhone 6S, iPhone 6S Plus, iPhone 6 and iPhone 6 Plus will support Wi-Fi Calling if they have iOS 9 installed.
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