Apple recently released the official version of iOS 15.1, along with iPadOS 15.1, WatchOS 8.1, and macOS 12.

To update your device from the iOS 15.1 beta system to the official version, follow these steps: remove the iOS 15 beta description file, restart your device, and wait for the iOS 15.1 official version update push.
SharePlay function and the support of HomePod’s non-destructive audio and Dolby Panorama audio audio.
SharePlay
SharePlay is a new way to share synchronized experiences in FaceTime with content from the Apple TV app, Apple Music, Fitness+, and other supported App Store apps
Shared controls give everyone the ability to pause, play, rewind or fast forward
Smart volume automatically lowers the audio of a movie, TV show or song when your friends speak
Apple TV supports the option to watch the shared video on your big screen while you continue the FaceTime call on iPhone
Screen sharing lets everyone on a FaceTime call look at photos, browse the web, or help each other out
HomePod non-destructive support
After upgrading to the iOS 15.1 system, the HOMEPOD supports the lossless audio and Dolby Panorama of Space Audio.
Camera
ProRes video capture using iPhone 13 Pro and iPhone 13 Pro Max
Setting to turn off automatic camera switching when taking macro photos and videos on iPhone 13 Pro and iPhone 13 Pro Max
Apple Wallet
COVID-19 vaccination card support allows you to add and present verifiable vaccination information from Apple Wallet
This release also fixes the following issues:
- Photos app may incorrectly report storage is full when importing photos and videos
- Weather app may not show current temperature for My Location, and may display colors of animated backgrounds incorrectly
- Audio playing from an app may pause when locking the screen
- Wallet may unexpectedly quit when using VoiceOver with multiple passes
- Available Wi-Fi networks may not be detected
- Battery algorithms updated on iPhone 12 models to better estimate battery capacity over time