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The Macropad is a USB keypad which has small OLED displays in each of the key-caps. The displays enable each key's legend to change based on user selection, or application context. The small 3x3 format was envisioned as an addition to a keyboard - to provide access to macros or application functions, without the need to remember key-binds. The concept could be applied to full-sized keyboards too, where powerful new functionality would be possible, such as support for multiple alphabets in general use.

The third version of the Macropad is based on Atmel's ATmega32U4 microcontroller, which was mostly selected for it's native USB HID support. The 32U4 sends USB keystroke packets to a connected computer, and manages the images displayed on the screens through a multiplexed SPI bus. Notable improvements over the second version include a new two-board design, a more reliable display/switch mechanism, increased flash storage for bitmap images, low-profile mechanical switches, and new (nicer) OLED displays.