Apple has given the public an inside look at their hundred-million dollar phone testing lab, which is quite incredible. The chambers are designed to replicate different types of wireless signals, such as cellular, WiFi, Bluetooth and GPS.
These chambers measure performance in free space, in the presence of materials simulating human tissue (“phantom” heads and hands, for example), and in use by human subjects. Over a one- to two-year development cycle, Apple engineers spend thousands of hours performing antenna and wireless testing in the lab.
Hit the source for more info and a video of the lab in action. Spolier alert: Those spiky things can move!