tvOS 26 is compatible with all Apple TV 4K and Apple TV HD models, but some of the new features are only available on newer models.The new Liquid Glass design with shimmery app icons and see-through elements is only visible on the Apple TV 4K (2nd generation) and Apple TV 4K (3rd generation).tvOS 26 takes Apple Music Sing a step further by allowing you to use your iPhone as a wireless microphone, with your voice amplified through the TV's speakers.
However, this functionality is limited to the latest Apple TV 4K (3rd generation).tvOS 26 is currently available as a developer beta.The update will be released later this year.