Apple TV.
Built for the Siri Remote and the 10-foot screen: focus-native layout, the tvOS Top Shelf with your recently added titles or the list you choose, an on-screen play and pause response, and a player interface that hides after five seconds.
Mac.
A native SwiftUI single-window app with a glass sidebar, in-window playback, full screen and Picture in Picture, a window transparency setting, and a Go menu: Command 1 to 8 for Home, Libraries, Favorites, Music, Live TV, Search, Downloads and Settings, Command F to find, Command P to play or pause, Command Option Left and Right to skip, Command Shift S and R for shuffle and repeat, Command Shift B for the music bar, Command Shift M for the mini player, Command N for a new window, Escape to close the player. Universal binary for Apple Silicon and Intel.
iPad.
An adaptive sidebar and detail layout across every iPad size, portrait and landscape, with Picture in Picture and the reader.
iPhone.
A one-thumb layout with Continue Watching first, offline downloads, Picture in Picture and AirPlay, and the phone as the remote for the living room: switch the Apple TV’s profile over Quick Connect.
Widgets and Live Activity.
Continue Watching and Now Playing on the iPhone Home Screen, transport on the Lock Screen and in StandBy, a Live Activity in the Dynamic Island while audio plays, a Mac Desktop widget and the tvOS Top Shelf. Widgets read from a sandboxed App Group and never open a network connection.
CarPlay.
Your Jellyfin library on the car screen, for audio from the head unit. Straight about it: the menus have been photographed drawing on a real head unit, and starting playback from the car has not been confirmed since the fix for it was written, so treat CarPlay as unproven rather than finished. Video on CarPlay is not advertised at all.