A giant QR code, posted by a fleet of drones in the skies over Shanghai, clearly demonstrates the scale of China's quadcopter industry. DJI, a domestic company, owns 80% of the global market for drones, and hundreds of UAV manufacturers are based in Shenzhen alone. Chinese drones are used in cinematography, industrial and agricultural applications around the world. They are deployed by police officers, farmers, and amateur photographers alike. A microscopic buzzing drone the size of a watch, a giant device that can fit four people, and hundreds of simple commercial drones that simply do their job - such objects can be found at the largest drone show in Shenzhen. According to SupChina, 369 companies are participating in the event and each has an average of five exhibits.