This conceptually simple demo has proved to be especially popular because it brings out the importance of low latency. A person wearing Google Glass plays ping-pong with a human opponent. The video stream from the Glass device is streamed to a cloudlet and analyzed on each frame to detect the ball and the opponent, compare their positions from the previous frame, and then to infer their trajectories. Based on this, the application guides the user to hit to the left or right in order to increase the chances of beating the opponent. To avoid annoying the user, the application tries not to give advice too frequently and only when it is confident of its advice.