Mirrorsoft's Tetris version was the very first commercial release of Tetris in the world. It was also released for the following home computer platforms: Commodore 64, ZX Spectrum, Amstrad CPC, Amstrad PCW, BBC Micro/Acorn Electron, MSX, Atari ST, and Amiga. Along with the version developed by Mirrorsoft's American sister company, Spectrum HoloByte, it was originally released before Andromeda Software was able to get a licensing deal with Elorg. A contract between Andromeda Software (the sublicensing party), and Elorg was eventually signed on May 10, 1988, which secured the legality of the products.