Backing Track Builder is a free Android app developed by JamString that allows you to create your own custom jam tracks. It includes 19 styles, such as blues, rock, metal, jazz, and pop, and you can choose the perfect chords, tempo, and style. All tracks use live instruments, which is a plus because midi sequencers and drum machines are not used. It's like having your own personal backing band!

With Backing Track Builder, you can create literally billions of possible jam tracks. You can get playing immediately with randomly generated chord sequences for rock, blues, and jazz. The app suggests scales and displays diagrams for guitar players. The custom tracks are great for improvising for guitarists, pianists, saxophonists, and other instrumentalists. The tracks are also very useful for songwriters.

The chords used include major, minor, minor7, major7, dominant7, minor7b5, altered dominants, add9, and diminished 7th. Backing Track Builder is a great app for anyone who wants to create their own jam tracks, and it's free to download from the Google Play Store.