Paper Dropbox UI is very good. But it isn't suitable when we take several notes every week. I use it to take notes in meetings. When I'm writing a note, the left panel should be improved. Some suggestions:
1) Include date (creation and last update)
2) Possibility to sort by creation date or last update.
3) Show "Favorite" icon when it applies.
4) Allow right click options: move, mark as favorite, archive...