What iPhone LiDAR does and how to use it

LiDAR stands for light detection and ranging. The scanner sends out invisible pulses of light and times how long they take to return after hitting surfaces. Those readings give the iPhone information about the distance and shape of objects in front of it. Cameras show what a scene looks like, while LiDAR adds information about how far away items are. Apple's augmented-reality framework, ARKit, can use those readings to create a rough 3D mesh of the physical environment, helping AR apps understand the position of floors, walls and other surfaces.

On supported Pro models, the sensor also assists the camera. Apple uses LiDAR for Night mode portraits and faster autofocus in low light. Apps built on Apple's RoomPlan framework can combine camera and LiDAR data to identify walls, windows, doors, furniture and other room features while creating a 3D model of an interior space.

Apple introduced the LiDAR scanner with the iPhone 12 Pro and iPhone 12 Pro Max in 2020. Since then it has remained a Pro-exclusive feature, appearing on every Pro and Pro Max generation through the iPhone 17 Pro and iPhone 17 Pro Max. Non-Pro iPhone models do not have the sensor. iPad Pro models since the fourth-generation lineup in March 2020 also include LiDAR.

A built-in way to try depth-assisted measuring is the Measure app, though Apple also includes Measure on iPhones without the sensor. To take a manual measurement, a user opens the app, moves the dot in the center of the screen to a starting point, taps the add button, moves the phone to the other end of the object and taps add again. Apple notes measurements are approximate, so they are better for quick estimates than for work requiring exact dimensions. On Pro models with LiDAR, Measure offers automatic edge guides, Ruler view and the ability to measure a person's height when the whole body is visible in the camera view.

For more elaborate uses, users need apps built to take advantage of the scanner. Apps using RoomPlan can scan interior spaces and produce 3D room models, while AR apps can use LiDAR depth data to place virtual objects more accurately in the physical environment. No switch is required, because supported apps call on the scanner when needed. LiDAR also supports an accessibility role: Detection Mode in the Magnifier app can detect nearby people, doors and furniture and provide information through sounds, speech or haptic feedback. Engadget noted Apple advises against relying on Detection Mode for navigation or in situations where an inaccurate result could cause harm.