There aren’t many Android phones with 4K displays. Basically the list starts and ends with Sony. But as long as the video you’re about to watch was downloaded in 4K and HDR, you can increase the quality to 2160p even if your phone screen doesn’t support the resolution. So if you want to consume your mobile bandwidth, we won’t stop you. Either way, you can adjust the playback quality by starting a video and then tapping on the three-dot icons at the top of the interface. When the context menu appears on your screen, press “Quality” and then choose the option you want.