Food delivery by drone is just part of daily life in Shenzhen

​My iced tea arrived from the sky. In a buzzy urban area in Shenzhen, China, sandwiched between several skyscrapers, I watched as a yellow-and-black drone descended onto a pickup kiosk by the street. The top of the vending-machine-size kiosk opened up for the drone to land, and a white cardboard box containing my drink was…