I've been searching an app that is able to represent information as a tree structure, so I found outliners. But all the outliners contain information as something like "tree-list", with expanding folder down and collapsing them up.
But what I'm really looking for is an app that is really similar to Windows Explorer or Mac Finder with the icon folder view but is intended to contain plain (some combination of text, pics etc.) information, not files, so that I could for example store a whole "slide" intended to matrices (I'm a math student) with text and pictures without need to store text in one file and pictures in the other.
I'd really love to have iOS 7-8-like opening style for folders, so that you could "dive into" some subject, but I guess, these are just dreams...
Is there something at least somehow similar to what I described? Preferably on Mac.