I originally needed a FIDO2 key. It now has a scientific calculator and plays pinball. Apparently, I cannot be trusted with spare flash storage.

EvilBundle now contains ten apps, loaded from microSD as .ekapp packages.

The useful half

• EvilLevel — an IMU-based bubble level, angle and slope measurement, with zeroing, hold and saved readings.
• EvilBench — electronics calculations: Ohm’s law, LED resistors, voltage dividers, RC filters, 555 timers and component markings.
• EvilUnis — unit conversion, including editable expressions, favourites, history and custom units.
• EvilCounter — multiple counters, adjustable steps, targets and timed sessions.
• EvilCalculator — a scientific calculator with powers, roots, trigonometry, logarithms, combinatorics, memory and an expression editor.

The “yes, this was necessary” half

EvilBlocks, EvilPinball, EvilBreaker, EvilInvaders and EvilRacer. Because debugging firmware apparently wasn’t enough of a time sink.

The screenshot sheet below shows actual .ekapp output captured in the firmware host renderer. It covers the current interfaces; it does not replace testing each app on the physical device.

EvilBundle remains in a private repository for now. This is a progress update, not a public bundle release.

I’m still open to interesting ideas for extending EvilKey. What would you actually use on a tiny touchscreen key that you already carry around? A practical tool, a game, or something I haven’t thought of yet?