By Dwight Silverman
AT&T has turned on a feature in Houston that allows its wireless customers to make calls over Wi-Fi when a cellular signal is not available or unreliable.
Wi-Fi Calling was lit up nationwide on Thursday. Earlier in the week, AT&T received a waiver from the FCC that let it enable the feature without providing teletype services for the deaf. The FCC requires carriers to make the traditional TTY systems work over Wi-Fi, but AT&T wants to use a more modern system. After promising to implement the newer Real-Time Text, or RTT, technology by 2017, the FCC granted the waiver.
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