Hey, thanks for checking Notesnook out.

I was myself a pen & paper user for notes. That is why I designed Notesnook organization system around the concept of notebooks & topics because they are very easy to get used to:

A notebook has multiple topics that can have multiple notes. (A single note can be under multiple topics - for flexibility).

As for markdown, Notesnook supports most of the markdown spec so you won't have any problem there.

I tried to make the app as simple and easy to use as possible because I am aware of how clunky and un-user-friendly many note-taking apps are. The aim is not to redesign (or reinvent) how to take notes but to improve & simplify it.