This blog provides a step-by-step guide on how to build a basic FaceTime clone app using the 100ms SDK in iOS. The application consists of two main views - ContactListView and FacetimeView. The ContactListView displays all contacts, while the FacetimeView is where video calls take place. Users can mute/unmute & end the call by clicking on options available at the bottom of the view. The 100ms SDK provides a simple way to integrate real-time communication features into iOS applications. By following this guide, developers can create their own video conferencing app similar to FaceTime.