Apple TV+ has the highest 4K streaming quality offered by a streaming service that supports 4K, according to testing conducted by FlatpanelsHD founder Rasmus Larsen. 

Larsen says that the ‌Apple TV‌+ offers higher quality 4K streaming than most iTunes movies, based on averages of the variable bitrate employed by the service. 


"See" had the highest bitrate of an ‌Apple TV‌+ show tested, averaging a 29Mb/s video bitrate and a 41Mb/s peak. 

"The Elephant Queen" averaged right around 26Mb/s for video bitrate, and other content, such as "Snoopy in Space" also performed well. 

According to Larsen, the ‌Apple TV‌+ offers 1.5 to 2x the video bitrate of a typical HD Blu-ray disc and around half of a typical UHD Blu-ray disc. 

Comparatively, Netflix's 4K bitrate appears to max out at right around 16Mb/s, though Netflix requires a 25Mb/s connection to stream 4K content.

Source: Macrumors