I’ve had a lot of people asking me about the digital version of Avengers: Infinity War that arrives one week from today so I decided to write this up to clear up any questions.
Next week when the digital version releases, you can purchase it in 4K UHD (with Dolby Vision HDR) via Vudu for $24.99, which is $5 more than the 1080p HD version. The 4K version is not available via iTunes or other digital store fronts…yet. When Apple rolled out their 4K Apple TV a big deal was made about them selling 4K movies for $20, and at this time Disney does not want to participate in that lower price point. So if you want to be sure to have the 4K version, Vudu is where to get it.
If you do have movies on iTunes, you can link your Vudu account to it via Movies Anywhere. That will link your purchases across iTunes, Vudu, Amazon, Fandango, etc. So even if you buy Infinity War on UHD via Vudu, you could still watch the HD version on iTunes or one of the other services.
As for where you can watch your Vudu UHD copy, this thread on the Vudu forums keeps an updated list. Right now the Vudu app will play the UHD movies in 4K with HDR on the Apple TV, Xbox One X/S, the Roku Streaming Stick, the Chromecast, and several smart TVs.