Show HN: I twisted my foot, so used an old phone's sensors into a recovery alarm

I twisted my foot while playing badminton. The doctor said the best way to recover is to keep it elevated. But I couldn’t really track whether my foot was in the proper elevated position or not.

So, I built a little app to solve this. Every smartphone already has motion sensors inside it. The accelerometer (measures movement in X, Y, Z directions) and the gyroscope (measures tilt and rotation). App reads these sensor values while the phone is strapped to my foot. It checks the angle continuously to know whether my foot is properly elevated or not.

If my foot is in a good elevated position, it shows me a green check. If it’s hanging down for more than a few minutes, the phone makes noise, vibrates, and flashes red to remind me.

It’s a fun little hack, but it actually helps me recover better by making sure my foot stays where it should. I ended up calling it “Elevation Police”. It's my personal ankle monitor that nags me for my own good.

discussion - https://x.com/the2ndfloorguy/status/1968306219371655227