Typora - A minimal Markdown reading & writing app.
StackEdit - Full-featured, open-source Markdown editor based on PageDown, the Markdown library used by Stack Overflow and the other Stack Exchange sites.
FocusWriter - FocusWriter is a fullscreen, distraction-free word processor designed to immerse you as much as...
Markdown by DaringFireball - Text-to-HTML conversion tool/syntax for web writers, by John Gruber
Scrivener - Scrivener is a content-generation tool for composing and structuring documents.
ghostwriter - A distraction-free Markdown editor for the desktop