That looks extremely similar to http://www.notebooksapp.com http://www.notebooksapp.com. Is that the same app sold differently? I use notebooks app and am happy

That looks extremely similar to http://www.notebooksapp.com http://www.notebooksapp.com. Is that the same app sold differently? I use notebooks app and am happy with it, always wanted a simple interface to my text/markdown files. But Quiver seems to have a few more options.