The screen was four-colors-of-gray but the device defined portable gaming and was enormous fun. Game Boy‚ which came out in 1989‚ was closely associated with the classic game Tetris when it debuted. Game Boy is the most successful video game system ever released. Since its introduction in 1989‚ Game Boy has sold well over 150 million systems worldwide. Originally bundled with the game‚ Tetris‚ this little handheld became an instant phenomenon.