If you use OneNote and have ever wanted Markdown, there is now a real solution: HydroMark is a Windows desktop add-in that brings genuine Markdown editing with live (WYSIWYG) preview into OneNote itself, while you keep OneNote's notebooks, sections, sync and password-protected security.

OneNote still has no native Markdown. If you want to write in Markdown without leaving OneNote, the two names you will keep running into are OneMark and HydroMark — both Windows desktop add-ins that render Markdown in place. They overlap on the basics, but HydroMark adds several capabilities OneMark lacks and undercuts it on price.