Before we get to the core of the input logic, let's first set a default value to our ActiveTouch variable. As we don't want the game to start running with ActiveTouch.Phase to be set to anything but canceled, we need to set it.

Add the following code to the Start function:

  /* Use this for initialization */
  void Start ()
  {
    ActiveTouch.Phase = TouchPhase.Canceled;
  }