T-Mobile to bring UMA (WiFi calling) to select Android handsets?

A leaked internal document suggests T-Mobile may be bringing a UMA-like feature to its Android handsets. For those not familiar with UMA, it is a feature found on T-Mobile’s handsets that allows a user to place a VoIP call via WiFi when cellular service is not available. UMA lets you use your T-Mobile number to place the call, instead of a third-party service like Skype which forces you to use an alternative number.

While the debut of UMA on T-Mobile’s Android offering  may cause many to rejoice, it could launch with a few important limitations including no support for UMA to GSM handoff. If you are talking on the phone via WiFi and lose your connection, your phone will not automatically switch to an available cellular signal. Once you drop  your WiFi connection, your call will drop, too.