move object x axis with finger touch

Hello, I have this code (below) well basic, which moves an object in the X axis but usually anywhere on the screen that I touch it continues moving this object. How to limit it to do that only when you touch the object, move it?

     if (Input.touchCount > 0 && Input.GetTouch(0).phase == TouchPhase.Moved) {
         Vector2 touchDeltaPosition = Input.GetTouch(0).deltaPosition;
         transform.Translate (touchDeltaPosition.x * speed, 0 , 0 * Time.deltaTime);
         }