The author migrated an Agora video call demo to Daily, a new video API platform. The migration involved several key changes, including updating the call client creation logic, replacing Agora's App ID field with a room URL, and changing the codec selection process. The author also updated the device selection functionality to use Daily's `enumerateDevices()` method and `setInputDevicesAsync()` method. Additionally, the author modified the video profile selection logic to use Daily's `setBandwidth()` method, which sets track constraints to the selected video profile. The migration also involved changing the user event handler setup, track subscription logic, and media update logic to work with Daily's API. Overall, the author aimed to demonstrate how to migrate an Agora app to Daily while maintaining its core functionality.