The 8BitDo Micro Controller is a Bluetooth gamepad with a 16 different inputs that you could fit into your back pocket. It costs $24.99.
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8BitDo Micro Bluetooth Gamepad
Play any game, anywhere. Nintendo Switch and Windows PC. 8BitDo controllers are designed to be as versatile as possible with each of your modern devices. Now with a 2-way mode switch, you can instantly pair your controller via Bluetooth.
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