The tutorial provides a comprehensive guide to building an iOS group messaging application using Objective-C and PubNub, emphasizing the challenges and advantages of designing such an app on a new platform. The author chose to create a group chat client to address the lack of dedicated tools for efficient large-group communication. Initially challenging due to XCode and Objective-C's complexities, the development process became more manageable with the use of model-view-controller frameworks and storyboards. The app features include user-friendly interfaces with bubble-like message boxes and intuitive design elements, allowing users to easily add or remove group members. The PubNub Data Stream Network plays a crucial role in facilitating seamless message sending and receiving, with a selective-listening feature that empowers users to choose their group members. The tutorial also highlights the recent release of a redesigned iOS SDK and provides resources like a migration guide and a GitHub repository with all the code needed to get started.