Teddy Hyde is the no compromises, extensible editor for GitHub (with a focus on Jekyll blogging).
Now with secure oAuth login. Supports two-factor authentication and never asks for your password directly.
Edit files directly on GitHub and publish to GitHub pages.
Preview markdown or asciidoc pages with just a swipe.
Intelligent editor knows about YAML Front Matter for Jekyll posts.
Upload images which are resized to a mobile friendly version and a thumbnail.
Add your own extensions to the editor using "Hyde Transformations."
See more at TeddyHyde.com or Blog.TeddyHyde.com.