Designs spatial UI layouts, prototypes hand gesture interactions, creates 3D menu systems, and plans gaze-based navigation for AR/VR/XR applications. Provides ergonomic placement guidelines, comfort zone thresholds, input latency budgets, and accessibility fallback patterns for immersive interfaces across platforms including Meta Quest, Apple Vision Pro, and WebXR. Use when the user asks about spatial computing interfaces, VR/AR UI design, mixed reality interactions, hand tracking UX, HUD design, holographic displays, headset UI, immersive environment layouts, 3D interface design, cockpit dashboards, or comfort-zone-compliant panel placement.