Touch screen poke examle

    public void PokeRigidBody()
    {
        //Make sure to import TouchScreenWrap.cs first
        if (TouchScreenWrap.touches.Length > 0)
        {
            var ray = cam.ScreenPointToRay(TouchScreenWrap.touches[0].position);
            RaycastHit hit;
            //Our finger poke on something with collider
            if (Physics.Raycast(ray, out hit)) { 
                if (hit.transform.GetComponent<Rigidbody>() != null)
                {
                    Vector3 offSet = hit.transform.position - cam.transform.position;
                    hit.transform.GetComponent<Rigidbody>().AddForce(offSet.normalized * Force, ForceMode.VelocityChange);

                }
            }
        }
    }