tell me about guest mode update and visions 2

Guest Mode Update

The guest mode feature in visionOS allows others to set up and try out Apple Vision Pro while preserving the owner's data and privacy. During a guest user session, the guest can use apps authorized by the owner, but there are some restrictions:

• HealthKit Data Access: Apps running for guests can access HealthKit data if already authorized but cannot request additional authorizations. The system will not present the authorization flow if requested, returning an error instead.
• Editing Restrictions: Guests cannot edit authorization, privacy, or security options in visionOS settings.
• Writing Health Data: Health data cannot be written to HealthKit during a guest user session to prevent mixing guest data with the owner's health data. Any attempt to write data will return an error, and apps should handle this by discarding the data and notifying the guest.

For more details, you can refer to the Get started with HealthKit in visionOS session.

VisionOS 2.0

VisionOS 2.0 introduces several new features and improvements:

• Scene Understanding: Enhanced fidelity in scene understanding capabilities, including detecting planes in all orientations and room anchors that consider the user's surroundings on a per-room basis.
• Object Tracking API: A new API allows attaching content to individual objects around the user, enabling new dimensions of interactivity.
• Hand Positioning: Developers can now decide if the user's hands appear in front of or behind the content, offering more creativity in app experiences.

For a comprehensive overview, you can check out the Platforms State of the Union session.

Relevant Sessions

1. Get started with HealthKit in visionOS
2. Platforms State of the Union
3. What’s new in device management
4. Customize spatial Persona templates in SharePlay
5. Design great visionOS apps