This is one of the best source codes for Online MP3, Music. It plays online songs as well as offline songs stored in the phone. The user can play music in the background as well as manage play from notification bar. Create your own music player app by doing the required changes that are stated in the document. The application is specially optimized to be extremely easy to configure, and detailed documentation is provided. Listen and enjoy unlimited songs.

Demo: https://codecanyon.net/item/android-online-mp3-with-material-design/17453836