// Play a sound if screen is facing downwards

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

using UnityEngine;
using System.Collections;

public class example : MonoBehaviour {
    void Update() {
        if (Input.deviceOrientation == DeviceOrientation.FaceDown)
            audio.Play();
        
    }
}

import UnityEngine
import System.Collections

class example(MonoBehaviour):

    def Update():
        if Input.deviceOrientation == DeviceOrientation.FaceDown:
            audio.Play()