To see if a movie can play in 4K on a compatible device, look for on the product page.
Apple just made it a little more attractive to rent movies off iTunes, especially for those of us with short attention spans who can't sit through a whole feature film in one sitting. Apple TV 4K features the powerful A10X Fusion chip which is a faster processor for a smoother gaming experience.
The tech blog gave mixed reviews to Apple's latest set-top box, but still awarded it an overall rating of 7.5, saying Apple is "the only company that has the combination of power and care to actually do it".
You will pay more at the beginning for the devices but in the long run it will be worth it, if you intend on regularly buying 4K content.
The lack of YouTube 4K comes down to the fact that Apple doesn't support the VP9 video coding format in either the TV or Safari browsers both mobile and Mac. If you want to get something in 4K, then it will simply cost the same as the HD version.
As you know, Apple has recently launched a new generation Apple TV named, Apple TV 4K. And despite its negative sentiment regarding its price, Time said the new Apple TV 4K is ideal for "Apple fans willing to pay a premium for convenience".
Apple's new 4K streaming device lets you watch movies and shows in the brilliance of 4K HDR quality. You can still watch the HD contents offline when there is no Internet connectivity. If you own an iTunes library that has HD content, Apple will upgrade everything you own to 4K for free.