Fire.app is described as 'menu bar only app for dead easy HTML prototyping. It supports Sass/Compass, Haml, ERB, Markdown, CoffeeScript, and more' and is an app in the Development category. There are more than 10 alternatives to Fire.app for Mac, Windows, Linux, Online / Web-based and Sass. The best alternative is Prepros. It's not free, so if you're looking for a free alternative, you could try Bourbon or Live.js. Other great apps like Fire.app are CodeKit (Paid), Crunch! (Freemium), Delivery (Free) and SiteFlow (Paid).