Now that the new Apple TV’s operating system has become a true software platform in its own right—joining iOS, OS X and watchOS—Apple can more easily than before add new features to the experience by way of software updates.
Like its predecessor, the fourth-generation Apple TV will put up a message when a software update is available. Sometimes, the notification may get delayed, or not show up at all.
Should this happen to you, you will need to check for updates manually and this tutorial will teach you how to do just that…. Read the rest of this post here