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.
Typora - A minimal Markdown reading & writing app.
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Dillinger - joemccann has 95 repositories available. Follow their code on GitHub.
Diaro - Multiplatform online diary and mobile app designed to record your activities, experiences, thoughts and ideas. Join now for free and keep your secret diary or diet, travel or life journal securely.
StackEdit - Full-featured, open-source Markdown editor based on PageDown, the Markdown library used by Stack Overflow and the other Stack Exchange sites.