I was one of the few who started using T-Mobile's UMA service way back in 2006 as part of a local T-Mobile beta test group and in those days the phones they had available for UMA calling were pathetic. A lot has changed in four years and we now have some great BlackBerry devices (Curve 8520, Curve 3G, and Bold 9700) and the Nokia E73 Mode that fully support UMA and offer customers a great experience. Today, T-Mobile announced that Wi-Fi Calling is finally coming to their Android lineup in the next few months, including support for the recently announced new T-Mobile myTouch with large 3.8 inch display.
In the past, users had the opportunity to pay $10 per month for the UMA service that gave you unlimited minutes when calls were handled through the WiFi UMA technology. That is now gone and the Wi-Fi Calling service of today is now a no-cost service that uses up your included plan minutes, but gives you the ability to make calls through WiFi in areas where you have low cellular signal.
THe solution for Android is powered by Kineto's Smart Wi-Fi application and it will allow Android T-Mobile owners to use WiFi for voice calls and text messages. Devices that T-Mobile specifically lists as getting support are the new myTouch and Motorola Defy, which are both expected this holiday season.