In “Hang the DJ,” the handheld device that pairs people is called Coach. It is a circular electronic device that assigns users romantic partners for fixed periods, monitors each relationship and eventually determines a prospective lifelong match.
Coach structures the lives of Amy and Frank, the episode’s central couple. Their first pairing lasts only 12 hours, while later matches last far longer. The device also tells users the system’s apparent success rate: 99.8 percent. That figure becomes important when the episode reveals that Amy and Frank repeatedly rebel together across simulated realities.
Charlie Brooker conceived Coach partly by comparing relationships to playlists on Spotify: the system gives people a sequence of experiences before selecting a final partner. The episode premiered on Netflix on 29 December 2017 as Series 4, Episode 4. A common mix-up is to call Coach a dating app, but within the story Coach is the physical interface for a larger matching system. Its name is also the name of the voice guiding users through the process.