AutoTheory makes you an instant master of music theory. Anything you play on your keyboard (midi or qwerty) will always be in key. Mozaic Beats’ AutoTheory software. Available for both Windows and OS X, AutoTheory sits between your MIDI keyboard and your DAW with a little pre-configuration, allows you to play complex chord sequences with a single finger, or constrain your melody playing to notes within a chosen chord or key/scale combination. You can leave the fingers of your right hand over the same five keys on your MIDI keyboard and, based on the chord you trigger with a single finger of your left hand, whichever notes you hit with your right will be harmonically ‘correct’ given the current chord.