Joplin - 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, tagged and modified either from the applications directly or from your own text editor.
Standard Notes - A safe place for your notes, thoughts, and life's work
Boostnote - Boostnote is an open-source note-taking app.
Typora - A minimal Markdown reading & writing app.
Day One - A simple journal application for the Mac, iPhone, and iPad. AboutTo learn more about Day One, see these two excellent reviews . PublishPublish is not available in Day One 2.
MarkText.app - Mark Text is a Markdown editor for Mac, Windows and Linux.