Today, Apple is releasing an Apple TV app for Amazon's second-generation Fire TV Stick and the Fire TV Stick 4K. Support for other Fire TV devices is coming later. With the app, you can watch anything in your iTunes library, as well as access the Apple TV+ streaming service that's set to debut next week.
The new app mirrors the functionality of the Roku app, which was only released last week. That means that while you can access content, you can't purchase or rent videos from within the app. You'll have to do that from your iPhone, or anything else that has an iTunes store, and then watch it through the app.
Obviously, this is part of a larger play by Apple to make its services more broadly available. Apple TV is available on Fire TV, Roku, various smart TVs such as those from Samsung, and it's coming to more. Apple Music has been available for Android since the beginning, and now there's a web app so you can access it from any platform. Even iCloud supports Files On-Demand on Windows 10 now.
The Apple TV app for Amazon Fire TV Stick will arrive in the U.S., Canada, the UK, Germany, France, Italy, Spain, and India. It will soon arrive for all other Fire TV models except for the first- and second-gen Fire TV, and the first-gen Fire TV Stick.