Here’s a nice in-depth guide by Vincent Ngo demonstrating how to implement some common design patterns in Swift and providing a nice overview on design patterns, and the possible uses for each specific pattern.

Specifically the tutorial covers the Singleton, Adapter, Decorator, Facade, MVC, Memento and Observer patterns, and in the tutorial you’ll build a simple music app using those patterns.

You can find the tutorial in two parts over on the Ray Wenderlich blog: Part 1, Part 2.