https://techcrunch.com/2019/11/01/apple-tv-now-live-with-one-year-free-for-new-ios-apple-tv-and-mac-purchases/

Apple has launched its streaming video subscription service, making available a varied and sizeable library of content immediately for subscribers. To access the service, you do need to sign up for a$4.99 per month subscription, but if you’ve purchased any new iPhone, iPad, iPod touch, Apple TV or Mac since the beginning of September, and you’re signed in to the Apple ID associated with those devices on those devices, the subscribe button should show that you get one full year of free trial service applied automatically.

Apple TV+ content lives in the Apple TV app that’s available across macOS, Apple TV, iOS and iPadOS devices, and which should be pre-installed already unless you’ve deleted it form your device or you’re running an older version of the operating system. Shows from the new program will then show up in a dedicated AppleTV+ row in the app’s home screen, as well as throughout the interface in various places.