Where to start to build for the Apple Vision Pro ?

To start building for the Apple Vision Pro, you can follow these steps:

Explore Apple's Human Interface Guidelines: These guidelines are a living documentation of the latest best practices for designing apps. They are a great resource to understand patterns and components specific to visionOS.
Use Design Resources: Apple provides Figma and Sketch kits with extensive libraries of native components. These can help expedite your prototyping process.
Recompile Existing Apps: If you have existing iOS or iPadOS apps, you can start by recompiling them for visionOS. This can quickly get your app running with a spatial UI layout, which you can then build upon to leverage the full capabilities of Vision Pro.
Utilize Native Frameworks: Consider using frameworks like ARKit and RealityKit to take full advantage of the device capabilities. This can help in creating immersive and interactive experiences.
Inspect and Debug: For web content, you can connect Apple Vision Pro to Web Inspector on your Mac to inspect DOM content, CSS rules, and use the JavaScript console for debugging.
Learn from Examples: Look at existing apps on the App Store for Apple Vision Pro to see how they have been designed and implemented. This can provide inspiration and practical insights.

For more detailed guidance, you can refer to the following sessions from WWDC 2024:

These sessions cover various aspects of developing for visionOS, from design principles to technical implementation.