T-Mobile US dramatically expanded the number of services included in Music Freedom, its zero-rated music streaming offering.

The operator has added 14 new services including Google Play Music, Xbox Music and Soundcloud. The likes of Pandora, Rhapsody and iTunes radio are already on board.  There a total of 27 streaming services now on offer via Music Freedom.

Zero-rated services typically involve operators or content providers footing the bill for data download costs.

T-Mobile US said in a statement: “Not only is Music Freedom available for T-Mobile customers at no extra charge, it’s also completely free for music streaming providers. No backroom deals. No paid prioritisation. Just you and your music unleashed.”

Whether, and how, such services are paid-for has become a hot potato politically in the US because of the intensifying debate over net neutrality.

T-Mobile US claims Music Freedom has been “wildly popular” since its release in the summer. The number of users streaming music each day has jumped nearly 300 per cent, equivalent to 66 million songs each day, it said.

The operator also said the service is a major draw to subscribers on other networks who have migrated to T-Mobile US.

Separately, the Federal Communications Commission issued a statement that T-Mobile US had reached agreement with the regulator that subscribers who run data speed tests on its network get accurate results, even when they are subject to data caps as part of their data plans.

As part of the agreement, the operator will send text messages to customers that will enable them to more easily get accurate speed information, place direct links to accurate speed test on their handsets, and revamp its own website disclosures to offer clearer information about real-life speeds.