> EDIT: Happy to see Milen's sibling comment about fixing breakage!! I realize you have to make a living -- is there a way to contribute for these new features (or is it a totally new app -- which is fine!).

I've considered the idea of letting other developers have access to the source code and help with the development. Unfortunately, I couldn't figure a way to make it fair - e.g., if someone starts contributing, do they start receiving a percentage of the proceeds? What's a fair percentage and what about multiple external contributors?

I could never come up with a workable model, so it's either fully open-source or proprietary. As I mentioned in another comment, I believe the way to go is an open data format which allows interoperability. This way there's no lock-in and competing apps (open or closed) can exist.

For what it's worth, the Monodraw data format is not secret, it's just compressed JSON. I haven't documented it because it's more of an implementation detail and I'd rather spend my very limited time on improving the product.

Hope that provides a bit more context.