Touch screen move - android

I have code, and in unity editor is done, but emulator doesn't work, if click anywhere on the screen game off. I have not idea how fix it. Thank you in advance.

 private var ray : Ray;
 private var rayCastHit : RaycastHit;

 function Update () 
 {
     if(Input.GetMouseButton(0)) 
     {
         ray = Camera.main.ScreenPointToRay(Input.mousePosition);
 
         if(Physics.Raycast(ray, rayCastHit))
         {
             transform.position.x = rayCastHit.point.x;
         }
     }    
 }