Groovy connects users by a music interest graph. Users can listen to music free for 45 seconds. A paid play ticket is necessary to listen full version of music, However, users can get it as a privilege by inviting friends to Groovy. As an interesting function as the music player, Groovy has a function of display lyrics. 39 Japanese labels participate in Groovy, and the number of the sold music exceeds 1 million now. This is very rare in the Japanese music industry. Because the right of the Japanese music industry is complicated, and the labels dislike Internet! :D
Groovy is only Android version now. However, of course DeNA is going to release the iOS version.