From the Simplenote weblog:
Today we’re excited to announce that Markdown support has been added to the latest update of Simplenote for iOS.
To enable Markdown for a note, just tap on the ‘Markdown’ button in the note info panel. You can then swipe on the note editor to view the Markdown preview. Once you’ve enabled Markdown for a note, all new notes you create in the future will have it enabled by default. We hope you enjoy this handy new feature!
I’ve been using Simplenote ever since I moved away from Vesper last year. It’s a great app, but unfortunately, this new Markdown support is far from robust. There’s no inline previews or shortcuts to help with the syntax, which I would consider to be essential features. I’ll continue using Simplenote as my notes app of choice, but I’ll keep my Markdown writing in Ulysses.