Amazon's Prime Video app finally supports Dolby Vision on tvOS and Apple TV 4K, although it still seems to be rolling out as it is currently limited to the first four episodes of The Rings of Power.
Update 30.1.2023: Dolby Vision is available again, this time for all episodes of The Rings of Power – who knows for how long it will last. The first episode of The Wheel of Time was also in Dolby Vision this weekend, but has since reverted to HDR10.
Update 18.1.2023: Amazon has for some reason disabled Dolby Vision again. We'll update again when there is new information.
After a 6-year hiatus following a partnership with Samsung for HDR10+, Amazon in September 2022 again began to offer select titles in Dolby Vision HDR. At that time, it worked on compatible FireTV devices and Smart TVs. It did not work on Apple TV 4K.

Four months later, Amazon has finally also added support for Dolby Vision on tvOS and Apple TV 4K. At the time of writing, the first four episodes of The Rings of Power stream in Dolby Vision while the next four are still in HDR10 on Apple TV 4K, suggesting that Amazon is still in the process of rolling it out. The Wheel of Time and Jack Ryan are also still in HDR10 on Apple TV 4K.

The Dolby Vision logo appeared on an LG OLED TV after starting playback of The Rings of Power episode 1-4 on Apple TV 4K and upon checking the actual video stream FlatpanelsHD confirmed that it is in 4K resolution and Dolby Vision with an average video bitrate of approximately 20 Mbps. Dolby Atmos also works. We are on the Prime Video app version 1.2.34 with Apple TV 4K (2021) and Apple TV 4K (2022) but we expect it to also work with the 2017 version.


 Prime Video in Dolby Vision on Apple TV 4K. Photo: FlatpanelsHD

Not related, but it is also worth noting that Amazon, like Netflix and Disney+, has started to abandon the antiquated fractional frame rate (23.976fps) in favor of the integer frame rate (24.000fps).

 Also read: Filmmakers urge TV industry to phase out fractional frame rates (e.g. 23.976fps)

With the launch of the Apple TV 4K (2022) box, Prime Video on tvOS also added support for HDR10+ (as detailed in our in-depth review) meaning that its tvOS app now offers HDR10, HDR10+ and Dolby Vision, depending on your TV model.

- Via: reddit