Nintendo released the Game Boy on April 21, 1989. The design team headed by Gunpei Yokoi had also been responsible for the Game & Watch system, as well as the Nintendo Entertainment System games Metroid and Kid Icarus. The Game Boy came under scrutiny by some industry critics, saying that the monochrome screen was too small, and the processing power was inadequate. The design team had felt that low initial cost and battery economy were more important concerns, and when compared to the Microvision, the Game Boy was a huge leap forward.