AT&T's HD voice, which also operates on VoLTE, is expected to interoperate with Verizon's HD Voice over VoLTE when it become available. But analysts believe it will take years for both carriers -- the two largest with more than 230 million customers combined -- to have such capability widespread in the U.S. with a multitude of users on HD Voice phones.
"HD Voice is a great feature as long as both ends support it," said Patrick Moorhead, an analyst at Moor Insights & Strategy. Given AT&T's success at other technologies, he said HD Voice won't necessarily be a "huge differentiator, so I don't think it's too big of a deal [to AT&T's success] in the long run."
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