1. A method of making a multi-touch input device for a computing device, the multi-touch input device comprising a body with a curved geometric feature, and a multi-touch sensor configured to detect touches on a surface of the curved geometric feature, the method comprising: forming on a substrate an array of sensor elements defining a plurality of pixels of the multi-touch sensor; forming the substrate into a shape that conforms to a surface of the curved geometric feature of the body of the input device; and fixing the substrate to the curved geometric feature of the body of the input device.