Great little app, very helpful for composing and actually hearing chord progressions back for those who don't have relative and perfect pitch. The only thing is that I would love for more customizations of the chords, namely inversions (even in combination with four note chords) and different rhythms that aren't 4/4. Right now, the root of the chord is always on the bottom. Inversions add a different color to the chord and are very widely used in songs and compositions. Some chords in the context of a certain progression just aren't the same sound without inversions. As for rhythms, it would be helpful for more control over how many bars a progression is and how many beats are in a bar. Right now, it's always 4 beats to a bar. Either 4 or 8 bars. I don't think adding different time signatures would be incredibly difficult nor adding custom length of bars any amount between (2-8). Also, adding chord changes within a bar would be awesome. That would add more complexity, sure, but the app for have so much value for making fully realized chord progressions for a song or composition. Other than those things, a solid app with lots of potential for improvement. I'm sure the inversions and rhythms features can be included in a future update.