According to the reports, the WiFi calling is coming to AT&T in 2015 but it seems as if this just isn't on their agenda or top priority list right now as opposed to the rest of the carriers and all this despite its huge footprint of unlicensed spectrum. AT&T has had an impressive history with Wi-Fi and it was the market leader in this segment in the US and among all other carriers, AT&T has had no problem at all in maintaining the biggest footprint of access points.