what is the difference between chromecast ultra and chromecast 3?
The Big Difference: 4K Ultra high definition (UHD or 4K) video is the main feature that bumps the Chromecast Ultra above the regular Chromecast. Chromecast Ultra can output streaming video at 3,840 by 2,160, while the regular Chromecast is limited to 1,920 by 1,080.