## TL;DR

The Device Orientation API provides accelerometer, gyroscope, and magnetometer data from mobile devices via DOM events: `deviceorientation` (rotation around 3 axes) and `devicemotion` (acceleration including gravity).

## Core Explanation

`deviceorientation` event provides `alpha` (z-axis, compass), `beta` (x-axis, tilt), `gamma` (y-axis). `devicemotion` provides `acceleration` (without gravity) and `accelerationIncludingGravity`. Values are in degrees or m/s². iOS 13+ requires user permission (`DeviceOrientationEvent.requestPermission()`). HTTPS required.

## Further Reading

- [DeviceOrientation Event Specification (W3C)](https://www.w3.org/TR/orientation-event/)