[dharness]

Beautifully clean, and simple! I've had my eye out for something like this, and I really do feel the other solutions are too big and clunky.

That said, I think the font is clutery.

The intro user flow is atypical and disruptive. I think it should start on this https://puu.sh/vy4pd/776dde20a8.png screen instead of inside a project. Then once inside maybe a little walkthrough or some guides?

Lastly I think the weird labels (Arps, counterpoint, melodic) on the left hand side are unintuitive for a novice. Also the addition of alt+drag to duplicate would be really nice ;)

But all in all, would use!

[mortenjorck]

Agreed on the typography: "Comfortaa" is not what I would consider a UI font.

As an alternative, OSS type family, I would recommend Lato (https://fonts.google.com/specimen/Lato). It's the family Slack uses, and I think it would look great in the UI for Helio.

[archagon]

Yeah — I just realized those labels were the default names for different layers, not special modes!