A free program for Android, by zhafardev.

Vita Alvia Mp3 Offline is an application for Android that lets you listen to songs offline. It’s the best way to keep yourself entertained when you’re on the road or just want to relax after a long day. You can choose from a variety of different categories and genres of music. All you have to do is download the application, install the songs you want to listen to, and start listening to them. The app will automatically find the songs for you and play them in the background. This application is the best way to listen to music without being connected to the Internet. It is also an excellent way to discover new artists and genres of music.