Playmaster, another official add-on, released in 1982, is an electronic device that keeps track of all player movement and dice rolls as well as what properties are still available. It then uses this information to call random auctions and mortgages making it easier to free up cards of a color group. It also plays eight short tunes when key game functions occur; for example when a player lands on a railroad it plays "I've Been Working on the Railroad", and a police car's siren sounds when a player goes to Jail.