Markdown New Tab - Write notes in Markdown directly in the 'New Tab' page
Typora - A minimal Markdown reading & writing app.
NotesHub - Fully cross-platform, markdown based note-taking app
Dillinger - joemccann has 95 repositories available. Follow their code on GitHub.
NotePlan - Make plans inside an individual markdown note for every day in your calendar. Use it as a journal for your daily tasks and plan todos in advance. For Mac, iPhone and iPad.
Caret - Better Markdown Editor for Mac / Windows / Linux