At this point, you can’t throw a rock without hitting a 4K, HDR-compatible television, at least if you̵
HBO made the announcement with version 18.104.22.168 of its Android app, which is now rolling out. That increases the resolution and dynamic range for Android phones, TVs and set-top boxes that support it. “Select Titles” also supports Dolby Atmos.
This is all in preparation for the very first piece of 4K content from HBO Max, the much-hyped streaming release of Wonder Woman 1984 on Christmas Day. At the time of writing, none of the service’s extensive catalog is available in 4K, but the new Warner Bros. movies in 2021 will all land in higher resolution, along with “even more 4K UHD titles.” Hopefully that includes some of the old HBO series too.
The new upgrade applies to the new Chromecast with Google TV (aka a new version of Android TV), the older Chromecast Ultra, the various SHIELDs from NVIDIA, and at least some of the TVs manufacturers have pre-loaded with the Android TV operating system (usually Sony). It may take a day or two for the update to be widely distributed.
Source: Google Play via 9to5 Google