When will AT&T allow wifi calling on your iphone when cell coverage is poor?

[iMore Question]

Why does T-Mobile allow wifi calling and not AT&T? When will that service be available on iOS8 for AT&T?

 

[SwitchBeach]

Why does T-Mobile allow wifi calling and not AT&T? ...

Because TMobile's network is inferior in coverage in a lot of places so they have needed to offer WiFi calling as a competitive advantage.