My interpretation of "flat" is how the latest Podcast App is. Everything is flattened out on the screen and all features easy to access. Instead of having controls hidden behind controls it's all laid out flat for the user.
https://www.macrumors.com/2013/03/2...custom-stations-playlists-and-icloud-syncing/
https://www.macrumors.com/2013/03/2...custom-stations-playlists-and-icloud-syncing/