Free trial: unlimited, supported by ads; purchased app, for $0.99, eliminates the ads.
This is one app that really needs to be
, and tried out: the developer bills this as the "thinking man's note pad," a free-form note-taking user interface, with rudimentary copy/paste [take that, Microsoft!]. You can start typing anywhere on a Mental Paper "page" and build lists, tables, check lists, trees and other formats. It seems to let you type thoughts almost randomly, keeps them separate, and lets you expand them by adding a checkbox, or other feature to further unpack the idea.