MP3-DJ Free is an Android music player developed by Torsten Hoffmann. It is a free multimedia application that falls under the Music and Radio sub-category. The app allows the user to play MP3 files and mix between two playlists with an adjustable fade effect. The user can choose between automatic or manual crossfading (FadeStart, FadeIn, FadeOut).

The app features a music library, two playlists, and a 5-band equalizer. The user can save and open playlists. However, compared to the full version "MP3-DJ the MP3 player," there are limitations. The music library can only hold a maximum of six tracks, and each playlist can only have a maximum of three tracks. Additionally, the equalizer is restricted.

Overall, MP3-DJ Free is a user-friendly app that provides basic music playing functionality. It's a good option for users who want to play and mix MP3 files on their Android device without any complicated features.