I build Lumecast, a live-streaming app (custom AVCapture pipeline feeding WebRTC). Three questions:   1. Does iPhone Duo support AVCaptureMultiCamSession — specifically front + rear simultaneously? Our co-casting feature would let a solo host fill two panes with their face and what they're looking at. How should a continuous capture session (live broadcast, can't pause) respond to camera direction changes as the device opens and closes? Is there a recommended pattern for swapping to the Virtual Front Camera mid-session without a visible gap for viewers?  3. Which cameras are available to third-party apps in each posture (folded / half-open / fully open), and does availability change at a specific hinge state? Goal: a host folds or unfolds mid-broadcast and their audience never sees a dropped frame.

is AVCaptureMultiCamSession supported on iPhone Duo — specifically streaming two cameras that face opposite directions simultaneously (e.g. .builtInInnerUltraWideCamera + .builtInOuterUltraWideCamera, or the Virtual Front Camera plus a backward-facing camera)? I noticed the article recommends single-input reconfiguration over multi-cam; is that a performance recommendation, or is opposite-direction multi-cam unavailable on this device? Our use case is a live co-cast where one host fills two video panes: their face and what they're looking at.