This document provides an overview of common object-oriented programming best practices and design patterns for iOS developers. It discusses obvious best practices in Objective-C like method naming conventions and notation. It also explains several classic design patterns like MVC, Singleton, Strategy, Decorator, and Delegate. Examples are given for how to implement patterns like Singleton, Strategy, and Decorator in Objective-C. The document aims to help iOS developers write code that is easy to understand, reuse, and change by using these practices and patterns.