I only have one external device that supports Dolby Vision, so I can’t confirm it’s only on the Apple TV 4K, but I watched Netflix’s Dolby Vision via the built-in app for the first time since purchasing this. It was miles brighter, and the colors were much more vibrant. In fact, with the Apple TV, as soon as Dolby Vision is enabled, all the apps on the home screen appear washed out and ugly. I compared the same iTunes Dolby Vision movies (Mad Max: Fury Road and Into the Spider-Verse) on my iPhone X (which supports Dolby Vision) to my A8G, and the TV didn’t come close to the vibrant colors, nor the brightness. Netflix Dolby Vision on the iPhone App and on the A8G’s app is beautiful and very bright. The A8G comes close to my phone’s brightness - and the colors on my phone match on screen… where they didn’t even come close on the Apple TV, so I’m not sure what to make of this.
I should note I did recently update the software/firmware to PKG6.6520.0252NAA, which brought it up to Android 8.0. I’m not sure if this nerfed anything. Anyone else seeing anything similar?