What is the purpose of LiDAR on your iPhone and how do you use it?

The LiDAR scanner in iPhone 12 Pro through 17 Pro emits invisible light pulses to map object distance and shape. It powers Night-mode portraits, low-light autofocus, and ARKit 3-D meshes for apps such as RoomPlan. Measure uses it for automatic edge guides, ruler view, and height estimation. Third-party AR apps employ it for precise virtual object placement and room scanning. Magnifier’s Detection Mode uses LiDAR to locate people, doors, and furniture, delivering auditory, spoken, or haptic accessibility cues.