Swift is an innovative new programming language for Cocoa and Cocoa Touch. Writing code is interactive and fun, the syntax is concise yet expressive, and apps run lightning-fast. Swift is ready for your next iOS and OS X project — or for addition into your current app — because Swift code works side-by-side with Objective-C.

But, The The Swift Programming Language
aslo can run on pcDuino 3 (Ubuntu) . They just are not different .

It really simple , just type command:

sudo apt-get install swift