In the USA you can teach GPS during private training but the checkride consists of navigation solely by reference to landmarks on the ground and DR. There is no provision for using the GPS during that portion of the flight test. However, recently we had a Commercial Pilot train with us for his Flight Instructor Rating and he was out on a solo flight when he got lost because he was in an airplane with no GPS for the first time. He had to land and call us to come get him!