UMA Comes To T-Mobile Androids… Almost!

It seems ?T-Mobile USA isn’t backing away from Unlicensed Mobile Access (UMA)?. I questioned company’s commitment to this technology, which gives them a unique leg-up over their rivals in terms of network coverage. In mid-September, a spokesman categorically told me that the company didn’t have any plans for UMA on Android (s goog).

Fast forward to today, and the company says it’s going to launch UMA-based Wi-Fi calling on Android smartphones. This will be made possible via an app that was released by T-Mobile’s UMA vendor, Kineto Wireless last month. I say almost, though, for two reasons: It’s not available on all Android handsets, and it doesn’t support in-call switching

It’s not very clear which Android devices will support the calling, apart from the new T-Mobile myTouch and Motorola DEFY (s mot). (I’m waiting to hear back from T-Mobile PR.) From what I understand, the Smart WiFi App from Kineto cannot be downloaded from the marketplace, mostly because it only works on specific versions of Android.

The Android app-based UMA offering is very different from the UMA offering on BlackBerry (s rimm) devices or the Nokia E73 (s nok). The BlackBerry devices have system-level integration, where the device automatically switches to and off the Wi-Fi network in the background. That seamless switching is one of the main reasons why T-Mobile sees 40 million calls over Wi-Fi every month.

The new app-based UMA has one advantage: It will go easy on the device battery. The chip-level integration often meant that the phones would ping-pong between Wi-Fi and regular cellular networks, causing the phone battery to drain faster than normal.

This is latest from TMobile PR:

Wi-Fi Calling for Android is built upon the same technology as UMA, but is a different implementation from our past offerings. While T-Mobile’s current Wi-Fi Calling solution which operates on BlackBerry smartphones, for instance, seamlessly hands off calls from T-Mobile’s network to Wi-Fi networks, Wi-Fi Calling for Android does not.

A pre-installed application from T-Mobile will allow customers to make and receive voice calls and SMS over an accessible Wi-Fi connection. This provides customers with better in-door coverage and in some cases may provide the ability to make voice calls in locations where they weren’t able to do so previously.

For consumers, Wi-Fi Calling for Android increases coverage and uses voice minutes. [NOTE: calls originate on Wi-Fi, but are carried across T-Mobile’s network once beyond the initial Wi-Fi connection.] T-Mobile also has plans for business which can help defer wireless minutes and provide cost savings.

Wi-Fi Calling will be available on the new T-Mobile myTouch, Motorola DEFY and others Android phones in the coming weeks. We are planning to expand Wi-Fi Calling for Android to as broad a selection of Android devices in our line-up as possible. Éclair (2.0/2.1) and Froyo (2.2) are the Android OS versions that currently support it.

Related GigaOM Pro content (sub req’d):