Spotify said Thursday that it now serves more than 3 million active paid subscribers per month, up from the 2.5 million subscribers it was serving in November. More than 20% of its active users pay for premium monthly access, the Financial Times said, which allows users to listen to an unlimited songs without ads or use Spotify on a smartphone. “We have achieved some pretty great results in terms of the ratio of paid users,” Spotify’s chief content officer and US managing director, Ken Parks said in an interview with the Financial Times. “We have an enormous internal effort to drive conversion and engagement with the service. We are very focused on growing in our existing 12 markets as well as expanding in other markets.” Parks also said that the company’s free-trial offer has helped convert users to paid accounts more rapidly. Spotify recently introduced “apps” for its service, which allows anyone, such as Rolling Stone or Billboard, to create playlists or add custom features.