T-Mobile US looks to have pulled out all the stops to beat AT&T to the VoLTE punch. In a blog posting yesterday (22 May), Neville Ray, T-Mobile US CTO, congratulated his team on launching VoLTE in the Seattle area, one day before AT&T is due to start its VoLTE service.
VoLTE from T-Mobile US is available for existing customers using LG G Flex, Samsung Galaxy Note 3 and Galaxy Light devices, although a software update is required.
And like the VoLTE platform which HKT is using in Hong Kong, T-Mobile takes advantage of eSRVCC (enhanced single radio voice call continuity) technology.
SRVCC enables call handover between LTE and 2G/3G networks, but the enhanced version has lower latency.
Other VoLTE features are much shorter call set-up times than conventional mobile, and the ability to maintain high-speed data connections when making voice calls.
HD voice is another VoLTE feature, which AT&T highlighted in its announcement last week, but Ray pointed out that T-Mobile US has been offering nationwide HD Voice since January 2013 – “something our competitors couldn’t do without VoLTE”.
Ray did not reveal where T-Mobile US would be launching VoLTE next, or which other devices the service would be available on.
AT&T said it would launch VoLTE in Illinois, Indiana, Minnesota and Wisconsin.
Verizon Wireless and Sprint, the other two nationwide mobile operators in the US, have still to launch VoLTE.