When comparing MultiMarkdown Composer vs StackEdit, the Slant community recommends StackEdit for most people. In the question“What are the best Markdown editors for OS X?” StackEdit is ranked 3rd while MultiMarkdown Composer is ranked 9th. The most important reason people chose StackEdit is:
StackEdit works within your browser. You need internet access to connect to the website, but once it's loaded, the site does not require an internet connection - you will be able to edit and save files locally. Additionally, you can use [Fluid](http://fluidapp.com) to turn it into a native desktop application.
Ranked in these QuestionsQuestion Ranking
Pro Multimarkdown Support
Not many popular markdown editors support multimarkdown syntax
Pro Multiple export options
You can export to HTML, PDF, LaTeX, RTF, OpenOffice, Microsoft Word, ePub, OPML.
Pro Table of Contents support
Generates a table of contents based on the headers in the Markdown file being worked on.
Pro Support for elastic tabstops
Elastic tabstops are used to align text automatically during writing. When there's a change in the text, MultiMarkdown Composer automatically aligns all lines both on the beginning and end of them.
Pro CriticMarkup support
Pro Optional Synchronized Scrolling
Hold a key down and get synchronized scrolling.
Pro Fast syntax highlighting
Pro Highly customizable
Pro Counts words, characters, lines
Pro Can show invisible characters
Pro Works online and offline
StackEdit works within your browser. You need internet access to connect to the website, but once it's loaded, the site does not require an internet connection - you will be able to edit and save files locally. Additionally, you can use Fluid to turn it into a native desktop application.
Pro No need to install additional software
StackEdit works directly from the browser, there's no need to install additional software as long as you have a web browser installed on your computer.
Pro Real-time preview
The preview shows in a collapsible pane on the right hand side.
Pro Multiple export options
Can export to .txt, .html and .pdf.
Pro Supports various Markdown flavors
Supports standard Markdown and Markdown Extra.
Pro Instant publishing
StackEdit allows pushing a document directly to a list of publishing or file storage platforms or any SSH server.
Pro Syncs via Dropbox and Drive
Files can be synchronized through Dropbox and Drive.
Pro Simple workflow
It is very easy to toggle between the preview and the editing windows. The black makes it a very focused writing environment. Of course it's possible to change that if needed.
Pro Great when in full-screen
Con Table of contents gets out of sync sometimes
If you keep the auto-generated table of contents open while you work it gets out of sync, meaning items in the table of contents (at the end) disappear until you restart the program.
Con The way the preview shows images is inconsistent
The preview is a bit inconsistent with images. Sometimes it shows the image correctly, sometimes it shows a blue question mark.
Con Cannot be accessed while being offline
Even though the editor itself works offline, you need internet access to open the website and the editor.
Con Saves files in browser's local storage
Local storage is limited and if the browser crashes the text can be lost.
Con Publishing to GitHub requires giving write access to repos
In order to publish documents to GitHub, StackEdit requires writing access to your repos, something which many people may not be comfortable with.
Con Lacks a good integrated spell checker
Uses the built-in browser spell checker which may not be as good as spell checkers other editors have. Depending on the browser, of course.