When comparing MacDown vs Letterspace, the Slant community recommends MacDown for most people. In the question“What are the best Markdown editors for OS X?” MacDown is ranked 5th while Letterspace is ranked 31st. The most important reason people chose MacDown is:
MacDown is a free and open source editor influenced by [Mou](http://25.io/mou/). It's released under the MIT license.
Ranked in these QuestionsQuestion Ranking
Pro Free and open source
MacDown is a free and open source editor influenced by Mou. It's released under the MIT license.
Pro Real-time split-screen preview
MacDown's main view is split into two panels. The user types on the left and the Markdown is rendered on the fly in the right panel. This helps users to better understand the way they are formatting their document.
Pro Markdown previews can be customized with CSS
You can use a CSS file to customize the rendered output and the file preview you are working on will display the rendered Markdown with the custom CSS styling on top.
Pro Supports syntax highlighting in fenced code blocks
MacDown has syntax highlighting support for various languages when writing code in fenced code blocks.
Pro Support for GFM
Pro Ideal for day-to-day programmers' work and MarkDown novices alike
Using MacDown for the notorious README.md use case gets you going without reading any manual or requiring any configuration values. Think of it as a sort of TextEdit for MarkDown files. Thus its shortcomings - neither powerful nor versatile - turn out to be a PRO for novices trying to jump on the MarkDown bandwagon. Open its help and you'll immediately find yourself editing the MacDown's MarkDown help file, a MarkDown primer with some MacDown menus and configuration added.
Pro Linking between pages
Unlike a few other editors, MacDown lets you link between markdown pages.
Pro Good auto-completion
MacDown has a good built-in auto-completion engine for Markdown symbols.
Pro Full featured iOS app
This was a iOS first app and that is clear. Great swipe bar interface on iOS.
Pro Simple, yet powerful interface
Keyboard shortcuts for basic text formatting. A few theme options. Full screen mode and swipe gestures.
Pro @mentions and #tags for easy organization
Pro Advanced Markdown support
Features Markdown support that many other text editors don't; such as Todo's ( -[x] ) and Strikethrough.
Con Not very versatile
MacDown is not very powerful or versatile. It's not customizable or extendable. This is what makes it so simple, but it's not for people who want more from their tools.
Con Frequently fails to update the display and/or flat out hangs
Must often restart MacDown.
Con The Markdown preview is rather heavy on the CPU
The Markdown preview needs a lot of resources to keep rendering on-the-fly after each keystroke. A single keystroke in the editor panel may trigger up to 5 seconds of max-CPU usage.
Con No in-app Markdown preview
You can export to PDF or HTML with formatting, but no preview in the Mac app.