Markdown by DaringFireball - Text-to-HTML conversion tool/syntax for web writers, by John Gruber
Journal - Organize all your ideas
Typora - A minimal Markdown reading & writing app.
Journalistic - A simple, yet powerful micro journaling app
StackEdit - Full-featured, open-source Markdown editor based on PageDown, the Markdown library used by Stack Overflow and the other Stack Exchange sites.
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.