In the upcoming iOS 14 system update, Apple has finally introduced support for Google VP9 decoding, allowing users to view YouTube videos in 4K resolution on new iPhones and iPads.
Due to the lack of VP9 support, iPhone, iPad, and Apple TV can currently watch YouTube videos up to 1080P. In the latest version of the tvOS test, Apple has added support for Google codecs — simply, users can watch YouTube clips “with their full 4K.”
It seems that the first beta versions of iOS 14 and iPad OS 14 are finally starting to support Google’s Ultra HD codec for some users. But currently, users on Apple’s mobile devices still can’t take direct advantage of the full 4K resolution. The resolution of video under 4K is 3840 x 2160, while the resolution of Apple’s largest iPhone 11 Pro series smartphone is 2436 x 1125, and the 12.9-inch iPad Pro has a resolution of 2732 x 2048.
In foreign tests, you can drop a 4K signal from an iPad or iPhone to a smart TV or other device via AirPlay. It is unclear whether 4K support will be retained in the full version of iOS 14 or iPad OS 14.