Editor’s note: The following review is part of Macworld’s GemFest 2013. Every day (except Sunday) from mid-July until late September, the Macworld staff will use the Mac Gems blog to briefly cover a standout free or low-cost program. Learn more about GemFest in this Macworld podcast. You can view a list of this year’s apps, updated daily, on our handy GemFest page, and you can visit the Mac Gems homepage for past Mac Gems reviews.

Many authors like use the Markdown format for writing because of its simplicity, portability, and ease of use. Lovers of the format will find themselves right at home with Erato 1.1.1 (Mac App Store link), which allows you to edit a Markdown file side-by-side with a live preview version of its compiled output.

While not entirely distraction-free, Erato makes it easy to detect mistakes early on, and the preview—which updates in realtime and can be turned off if you so desire—gives you a better idea of the general flow of the text you’re writing.

Erato lacks some basic features that can be found in just about every single one of its competitors, although it does support Github-flavored Markdown syntax. Still, if you find simplicity without pretension appealing, Erato does its job admirably well at a very reasonable price.

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