If you want to try the next major version of tvOS on your Apple TV, you can now download the pubic beta. Dolby Atmos is the most significant new feature.
tvOS 12 public beta
The next version of the operating system for Apple TV will be released this fall. Developers have had access since early June and with the public beta you can also get onboard.
Especially users with Dolby Atmos have reason to update. Purchased iTunes movies will be upgraded free of charge to Dolby Atmos if the movie studio has made an Atmos soundtrack available. As reported by FlatpanelsHD, users have had luck with Blade Runner 2049. Vudu also offers titles in Atmos on Apple TV 4K. Netflix will join the party later.