For Unity3d. Intended to be used as a member property of component. Simple Gyro input controller that tracks the relative rotation of the device while the screen is being touched.

GyroControls.cs

[System.Serializable]
public class GyroControls{	

	public Vector3 clampRotation = new Vector3(30f,30f,30f);
	public Vector3 deadZone = new Vector3(3f,3f,3f);

	Quaternion startRotation;
	bool touching;
	Vector3 mRotation;

	public void Update(){
		bool touchingNow = Input.touchCount > 0;
		Quaternion rot;
		Vector3 eulerRot;
	
		if( !touching && touchingNow ){
			startRotation = Quaternion.Inverse( Input.gyro.attitude );
		}
		touching = touchingNow;

		if( touching ){
			rot = startRotation * Input.gyro.attitude;
			eulerRot = Quaternion.Inverse(rot).eulerAngles;


		}
		else {
			eulerRot = Vector3.zero;
		}

		if( eulerRot.x > 180 ) eulerRot.x -= 360;
		if( eulerRot.y > 180 ) eulerRot.y -= 360;
		if( eulerRot.z > 180 ) eulerRot.z -= 360;

		eulerRot.x = Mathf.Sign(eulerRot.x) * Mathf.Max(Mathf.Abs(eulerRot.x)-deadZone.x,0);
		eulerRot.y = Mathf.Sign(eulerRot.y) * Mathf.Max(Mathf.Abs(eulerRot.y)-deadZone.y,0);
		eulerRot.z = Mathf.Sign(eulerRot.z) * Mathf.Max(Mathf.Abs(eulerRot.z)-deadZone.z,0);

		eulerRot = Vector3.Min( eulerRot, clampRotation );
		eulerRot = Vector3.Max( eulerRot, -clampRotation );
		Vector3 input = new Vector3( eulerRot.x / clampRotation.x, eulerRot.y / clampRotation.y, eulerRot.z / clampRotation.z );

		mRotation = input;
	}

	public Vector3 rotation {
		get {
			return mRotation;
		}

	}

}