Empty reply from server
string dataGetURL = "http://localhost/HighScore/GetScore.php";
WWW getData = new WWW(dataGetURL);
yield return getData;
if (getData.error != null)
Debug.LogError("There was an error getting the high score: " + getData.error);
For future users, It just worked by changing the localhost into my Computer IP.
string dataGetURL = "http://your IP Address/HighScore/GetScore.php";