Head Radio is the only radio station from GTA 1 that appears in other games; it was also a station in Grand Theft Auto 2 as well as in GTA III and Grand Theft Auto: Liberty City Stories.
There are unused graphics for a helicopter. When spawned in-game, it moves on the ground like a car.
After the PlayStation version's successful release, development began on a port for the Nintendo 64. Grand Theft Auto 64 was rumored to have graphical enhancements and new missions, but was cancelled without ever having a public appearance.