The e-commerce giant just announced a variety of updates to its Fire TV product line. The newest Fire TV set-top box, a flat, plastic box that plugs into your TV and offers a variety of internet video content, now supports 4K Ultra HD video, a claim that Apple can’t make with its own set-top box. (You’ll have to be watching 4K content, on a 4K TV, to really reap the benefits of this, but at least the option is there.)
Source: Amazon’s answer to Apple TV: a Fire TV box with Alexa and 4K video support | The Verge