A website that allows you to write and run Swift from within the browser. RunSwift gives you a simple editor where you can write Swift, and a console that displays output. While you cannot import abitrary modules, a small subset of Foundation is included making it a great place to quickly try out some Swift without firing up Xcode. There is also a step-by-step interactive lesson that will walk you through the basics of the Swift language while allowing you to continue to play in the editor. RunSwift is also fully responsive so you can even write Swift on your iPhone or iPad!