Gyroscope is an action video game published by Melbourne House in 1985 for a number of home computers. It is based on the Atari arcade game Marble Madness.
The gameplay is very similar to Marble Madness except the player controls a spinning gyroscope rather than a marble. Melbourne House would go on to publish the official Atari ports of Marble Madness (DeLuxe Edition) for the ZX Spectrum and Amstrad CPC but these were entirely new versions, unconnected to Gyroscope (being coded by John F. Cain rather than the Catalyst Coders).
The game is presented in isometric 3D. The player must guide the gyroscope from the top of the course to the bottom within an allotted time limit. If the gyroscope topples off the edge, a life is lost. Hazards on the course include potholes, aliens and glass slopes which cause the gyroscope to spin in random directions. There are five courses comprising four screens each. The gyroscope had to land on a marked square to complete each level.
Source: Wikipedia, "Gyroscope (computer game)", available under the CC-BY-SA License.