cant load mp4 movie file from Application.persistentDataPath in IOS

I was trying to download movie(mp4)file from webserver and create file into

Application.persistentDataPath

and play the movie file ( mp4 file).

private void Awake()
    {
        //mediaplayer gameobject. use this to Play movies.
        uniplayer = GameObject.Find("UniversalMediaPlayer").GetComponent<UniversalMediaPlayer>();        
        _filePath = Application.persistentDataPath + "/Unity.mp4";
    }

    public void downloadBtn()
    {
        StartCoroutine("moviedown");
    }

    public IEnumerator moviedown()
    {
        if (!Caching.ready)
        {
            yield return null;
        }
        var www = new WWW("http://cupzip2016.cafe24.com/bomsoft/AssetBundleTest/Unity.mp4");   

        while (!www.isDone)
        {
            percentslider.value = www.progress;
            movieDnBtn.text = (www.progress * 100).ToString("##.#") + "%..";
            yield return null;
        }
        if(www.isDone)
        {                
            Handheld.Vibrate();
            FileStream stream = new FileStream(_filePath, FileMode.Create);
            stream.Write(www.bytes, 0, www.bytes.Length);
            stream.Close();
            percentslider.value = www.progress;
        }
    }

    public void pressPlaybtn()
    {
        uniplayer._path = "file://" + _filePath;
        uniplayer.Play();
    }

this code works on android/ window/ mac but Iphone does’nt working at all

I have no idea .I don’nt know why only IOS does not working … I spend more than 10 days to solve this problem!! but I could’nt …

This is old but WWW only works with ogv files in iOS and then only in full screen. See Unity documentation.