macOS Monterey 12.1 beta reveals a new addition- the SharePlay feature which is available for users to try.

The beta version of macOS Monterey 12.1 has been seeded to developers. SharePlay is a new feature that allows FaceTime users to stream their screens, music, TV and movies, or share them while using an iPad or iPhone.
SharePlay was initially expected to launch alongside iOS 15, but Apple had it delayed. After several beta versions, SharePlay has now appeared on tvOS 15.1, iPadOS 15.1 and iOS 15.1. App support is largely limited to Apple Fitness+, Apple TV+ and Apple Music. However, developers can take a look at the technology and have it integrated to their respective apps.
Apple announced that SharePlay can be built across platforms using GroupActivities and without having to rely on its development profile. More information about SharePlay can be found on Apple’s official developer page.