Input.deviceOrientation

public static DeviceOrientation deviceOrientation ;

설명

Device physical orientation as reported by OS. (Read Only)

using UnityEngine;
using System.Collections;

public class ExampleClass : MonoBehaviour
{
    AudioSource audio;

    void Start()
    {
        audio = GetComponent<AudioSource>();
    }

    void Update()
    {
        if (Input.deviceOrientation == DeviceOrientation.FaceDown)
            audio.Play();
    }
}