While the TV app appears to be rolling to users in Canada and Australia starting tonight, it is not yet available for all users, nor is it functional. MacRumors reader John, who is from Australia, said the TV app has shown up on his fourth-generation Apple TV but isn't loading content as of yet.
Apple last Tuesday announced that the TV app would expand to Australia and Canada "later this month," but did not specify exactly when it would be released. Presumably, the app will become functional tomorrow after iOS 11 and tvOS 11 become available to the public.
The TV app, which has been available in the United States since December of 2016, is designed to provide a centralized way to access all of the different television channels and content available through dedicated apps from major networks like HBO, CBS, NBC, FOX, and more.
The TV app allows users to play TV shows and movies with a single click, and it syncs content across devices so it's always possible to pick up a TV show or movie being watched on one device on another device. Apple has also introduced content recommendations to help users discover new TV shows and movies to watch.
More than 60 services are supported by the TV app, but with the expansion to new countries, Apple plans to add support for additional local content
Later this year, Apple plans to expand the TV app to France, Germany, Sweden, Norway, and the UK.