T-Mobile has decided to set music streaming services free. The “Un-carrier” said it will offer subscribers unlimited access to the top six music streaming services including Pandora, Slacker, iHeart Radio and Spotify without incurring data charges on their 4G plans. Samsung’s Milk Music and the forthcoming Beatport music app from SFX – will also be offered to customers free of data charges. The announcement recognizes the growing popularity of streaming music as well as the fact consumers have a tough time knowing how much data such services will use. Consumers increasingly are tuning in Spotify and other music services to listen to millions of songs on-demand. Global revenues from music subscription services exceeded $1 billion for the first time last year, according to the IFPI, the music industry’s international trade group.