5 stars: If you're an amateur musician, you're gonna LOVE this. It's a very simple way to generate the rudiments of a song. You select your instruments (piano, bass, guitar, drums, etc.) and the basic pattern that each instrument will play, and then you just build a chord progression by adding measures of specific chords. You can build an entire song in less than a minute. Its great for creating backup / accompaniment to play or sing along with.
4 stars: Contains an astounding range of styles and presets and has no adverts and it's free. You can't save unless you pay but just screenshot it. You can set any key in all of the main modes and choose any chord regardless of the settings e.g. D major chord in C major (Ionian) scale. It's an amazing app and I'm tempted to buy the full version to support them.
3 stars: Not bad, but: 1) instrument volume is broken, changing an instrument's volume indirectly affects all other instruments 2) there are dozens of choices for style but none are great, there should just be a few of the most important grooves well made. However it's the best backing track app I can find on Android, better than Band Practice and Backing Track Builder
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