Mastering Swift 2 Programming (Video 53)

This video tutorial discusses the Singleton pattern, a design pattern ensuring only one instance of a class exists during an application's lifetime. It covers the implementation of Singleton in Swift, highlighting best practices recommended by Apple. The video also addresses the controversy surrounding Singletons, noting their potential to complicate testing and encourage poor design choices. Additionally, it explores concurrency issues that can arise with Singletons and demonstrates how to resolve them using Grand Central Dispatch.

What are the potential issues when multiple threads attempt to access a Singleton instance?

How can Grand Central Dispatch be used to manage access to a Singleton's resources?