Mixtapes are albums made by artists and distributed for free without a record label, being a great way to get your name out there. Well there is a developer named Carson Bath on the Play Store that releases apps that just move these mixtapes to your SD card for playing with any music app of your choice.
This developer has mixtapes from many artists, including Wiz Khalifa, Tyga, Childish Gambino, and more. You should really check it out. It was an easy way of getting Royalty by Childish Gambino for me. Of course, all this is 100% legal. So hit the source link and get downloading!