A few weeks ago, we shared the news that AT&T was delaying adoption of the WiFi calling feature in the new version of Apple’s operating system for mobile devices. The carrier said that it was awaiting FCC approval of the feature, which other carriers have enabled already. Now AT&T has tattled to the FCC on those other carriers, pointing out that they should be waiting for approval too.

The problem isn’t with using smartphones to make calls over WiFi: the problem is that the FCC hasn’t approved that feature for use with devices that some people with hearing and speech disabilities use with iPhones, teletypwriters or TTYs.

The TTY became widespread technology in the ’70s and ’80s, and other technologies, including video chat, video relay, and text messaging have come to replace it for more affluent and tech-savvy people. Yet TTYs remain in use, especially among older people who have always used them. Someone could theoretically use one with an iPhone, and the FCC requires that they be compatible.

AT&T wants to be sure that they have approval to allow TTY users to use the devices over WiFi calling, especially when calling 911. (Texting 911 is possible, but available in very few markets.)

That’s what they tattled about to the FCC: AT&T has an alternate technology called Real-Time Text that works more reliably over WiFi, and they requested a waiver to use that protocol instead of TTY. Other carriers, notably T-Mobile and Sprint, let customers use the feature without waiting for a waiver.

AT&T says T-Mobile and Sprint Wi-Fi calling violates disability rules [Ars Technica]

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