Spivo is a cutting-edge tennis training tool designed to give players instant acoustic feedback on their swing technique. By producing a distinct whistle sound when a shot is executed correctly—especially with topspin—it helps players fine-tune their form in real time. Trusted by elite coaches and endorsed by the German Tennis Federation, Spivo uses biomechanical principles to simplify complex movements, making it easier for both beginners and pros to master powerful, precise shots.