MarkdownMail for iPhone and iPad allows you to write articles in the Markdown format. You'll then be able to export the markdown in an email or send beautifully formatted HTML emails from the app itself. For those who aren't familiar with what markdown is, let's cover that first. Markdown is a markup language created by John Gruber and Aaron Swartz. It's extremely easy to learn and extremely convenient and efficient for publishing online. Markdown will basically convert your content into valid and properly formed XHTML. You don't have to deal with HTML tags and code. Markdown will take care of that for you.
Read on for a quick walkthrough of MarkdownMail which is currently available for both iPhone and iPad.