Metanota is described as 'beautiful OSX client and editor for creating and managing notes using the well known SimpleNote cloud service. Other note-taking cloud providers will follow shortly' and is an app in the Office & Productivity category. There are more than 50 alternatives to Metanota for a variety of platforms, including Windows, Android, Mac, Online / Web-based and iPhone. The best alternative is Joplin. It's not free, so if you're looking for a free alternative, you could try Standard Notes or Evernote. Other great apps like Metanota are Simplenote (Free, Open Source), CherryTree (Free, Open Source), Trilium Notes (Free, Open Source) and Cryptee (Freemium, Open Source).
Joplin is a free, open source note taking and to-do application, which can handle a large number of notes organised into notebooks. The notes are searchable, can be copied, tagged and modified either from the applications directly or from your own text editor.
Colorful & powerful sticky notes app for Windows & Phones. Set reminder alarms, attach them to any website or document, organize them using folders/tags, sync sticky notes between devices & send notes across LAN or to any contact across the globe.
The notes app for creative work. For the research, thinking and planning behind your next great piece of work. # Collect your thoughts Milanote is a place to put it all together. See your ideas, notes and research side by side.