[wiggler00m]

> "...what’s the catch?"

I'm still looking for a catch. I will say it's not clear if the developer(s) are still focused on this, unfortunately. I hope they continue to develop it and attract more users. Also, I'm not sure if the .kanbanier file type is convenient if you want to export data.

> "Do you know of any other apps that use this App Store + native iOS and macOS client model by the way? I’ve never seen this done properly before (i.e. no electron, cross platform UI)"

I like this model too. The native BOOKS application for Mac OS X and iPad equivalent seems similar. It syncs well with icloud in my experience.