Daily, a platform for creating custom apps, has released a tutorial series on how to build a custom fitness app with real-time video capabilities. The first part of the series focused on setting up the basic feature set, and this second part delves into two specific features: adding "Mute all" buttons for student microphones and cameras, and auto-muting the participants' devices when the instructor starts the class. By utilizing Daily's open-source examples repository and understanding how to use the `updateParticipants` method, developers can implement these features in their fitness app, enhancing the user experience for instructors and students alike.