Looks great but also seems that it's a one size fits all editing experience and a couple of questions come to mind from a quick look...

Can TinyMCE be customised for users?: I usually customise the editor matching the fonts and styles to the site's frontend and giving them custom styles they can apply to element, also use the TinyMCE Advanced plugin to give them extra tools like table editing as well. Doesn't appear that any of this will flow through to the app.

Custom post types: Am I right that only 'standard' posts and pages are editable via the app right now and that custom post types will jump out of the app to browser?