Nintendo · Game Boy · 1989
The original Game Boy's control scheme — a d-pad, two face buttons (A and B), and Start and Select — was deliberately minimal, optimised for one-handed thumb operation and designed to survive the rough treatment of a children's portable device.
The Game Boy's controls were a direct port of the NES controller's essential inputs stripped to the minimum required for portable use. The d-pad came from the NES controller design and the Game & Watch precedent; A and B matched the NES's primary face buttons; Start and Select fulfilled their NES functions of pausing and option access. The layout was arranged for pure thumb operation — both hands held the unit while both thumbs handled all inputs, with no inputs requiring index finger operation. The result was a controller that placed no ergonomic demands on players: children, adults, and elderly players all adopted the same natural two-thumb grip without instruction. The Game Boy's games were designed within these constraints — Tetris required only d-pad, A, and B; Pokémon used all four inputs plus Start for menus; Super Mario Land mapped its controls to the same layout as Super Mario Bros. The Game Boy Pocket (1996), Game Boy Color (1998), and Game Boy Advance (2001) all retained this input set, adding only L and R shoulder buttons on the GBA to support SNES-era ports without disrupting the fundamental layout.
Demonstrating that a minimal, carefully chosen input set could support a decade of diverse software without requiring hardware revision.
Gunpei Yokoi's brief for the Game Boy was a device that could be carried in a schoolbag and operated by a child on a bus. These constraints directly shaped the control design: inputs had to be operable with thumbs while the device was held in both hands, without requiring the player to look at the controller. The d-pad's cross shape was already proven on the Game & Watch for exactly this use case. The A and B buttons were placed at a slight diagonal from each other on the right side — close enough for the thumb to move between them without repositioning the grip, but far enough apart to make inadvertent presses of the wrong button unlikely.
The button materials were chosen for durability and tactile clarity: rubber dome switches under each button provided a consistent click that the player could feel without seeing, allowing eyes-forward play without any risk of pressing the wrong input. The d-pad used the same rubber membrane system. Both were tested by Nintendo's hardware team for a minimum of ten thousand presses before being approved, a durability threshold that reflected the expected use pattern of a child's toy rather than a fragile consumer electronic. Game Boys from the original 1989 production run regularly remain functional today — a hardware durability record that owes as much to the input mechanism's robustness as to the device's electronics.
The Game Boy's two-button face layout — A and B — created an interesting design challenge that its software library handled with notable creativity. With only two face buttons plus Start and Select (which were used primarily for pausing and menus rather than gameplay actions), developers had to design all game interactions around A and B. Tetris assigned A to rotate clockwise and B to rotate counterclockwise — a two-button vocabulary that matched the game's complete action set. Pokémon used A to confirm and B to cancel in menus, a convention so natural that it persisted into three-dimensional Pokémon games on hardware with many more buttons.
Games requiring more complex action vocabularies adapted by making A and B context-sensitive: in Super Mario Land, A jumped and B ran, matching the NES Super Mario Bros. layout exactly. In Metroid II, A fired and B jumped — an inversion that confused players who had memorised the first game's layout. The two-button constraint produced creative solutions that sometimes felt elegant and sometimes produced awkward compromises, but the library's overall success demonstrated that input complexity was not the primary driver of gameplay quality. Pokémon — the best-selling Game Boy game at over 30 million units — was entirely playable on two face buttons, and its social mechanics made it the defining handheld game of the decade despite input constraints that contemporary designers would consider severely limiting.