I’m not the best person to explain what Markdown is, but if you do a bit of searching you will likely discover the wonders of it. Designed to add formatting to plain text transparently, I think its a great way to keep your text simple while producing well formatted documents for the web and for print.
On the iPhone and iPad I’ve been using Byword pretty faithfully for Dropbox-sync’d text glory. You can preview your documents in Markdown with one push. One thing I wish it had is the extensive (all document) sync every time you open the app the way PlainText does, but maybe that will come soon.
On the Mac, I’ve used the trusty Smultron for quite some time, but the syntax highlighting for Markdown was pretty limited in version 3. I like Smultron’s ability to have many documents loaded up on the left hand side, which makes it much like Byword or PlainText on iOS. Most Markdown editors on the Mac don’t seem to employ tabs for some crazy reason.
My app of choice for now is the fairly unknown Valletta, which allows you to type in plain text on the line you’re writing, and conveniently preview other lines marked down that you haven’t selected, as seen in the screenshot. To me this makes the most sense, as I’m not toggling back and forth to preview, or have a seperate window taking up screen space. The more I thought about it, the more I realized this is also defeats the intention of markdown (to create readable marked up documents) but I still think its a nice way to edit.
What do you use to edit Markdown?