The final version of tvOS 12 is now available for all supported Apple TV 4 and Apple TV 4K devices. With this release, Apple has made minimal changes that introduce things like single sign-on, underlying improvements that make it easier for developers to create more powerful third-party apps, and Dolby Atmos support that instantly approves the experience for those with compatible hardware.
How to install tvOS on your Apple TV
The tvOS 12 update will be pushed to your Apple TV automatically over-the-air (OTA), but you can also manually install the update using iTunes on your computer. If you have setup your Apple TV to update automatically, you wont need to do a thing. If you prefer installing updates manually, just follow the steps below:
Step 1) Press the Home button on your Apple TV remote and go to your device's Home screen
Step 2) Launch Settings on your Apple TV
Step 3) Go to System > MAINTENANCE > Software Updates.
Step 4) Click on Update Software and wait for Apple TV to check for new software updates.
Step 5) Once the update is available, the Apple TV will inform you, and request confirmation to install it.
Step 6) Accept the confirmation, and click Download and Install.
Step 7) Wait for Apple TV to download the update, and click 'Update Now' when the download is complete.
Step 8) You will see the Apple Logo and the update process will kick off.
Once completed, the Apple TV will inform you that it is up to date.