Gyroscope.rotationRate
var rotationRate: Vector3;
Description

Returns rotation rate as measured by the device's gyroscope.

The rotation rate is given as a Vector3 representing the speed of rotation around each of the three axes in radians per second. This is the value as it is reported by the gyroscope hardware - a more accurate measurement that has been processed to remove "bias" can be obtained with the rotationRateUnbiased property.
	var shakeSpeed: float;
	var shakeSound: AudioClip;

	function Update() {
		// Play a sound when the user rotates the device quickly.
		if ((Input.gyro.rotationRate.y > shakeSpeed) && !audio.isPlaying) {
			audio.PlayOneShot(shakeSound);
		}
	}