They also sell physical hourglasses if you don't want to be interrupted by a distracting beeping thing once the timer is over, especially if the activity you're trying to start with a pomodoro requires concentration like coding.

I attached an ESP32 and accelerometer to an hourglass for this purpose, calling back to https://pypi.org/project/gitime/ to log pomodoros on my dev machine.

If it was overengineered and trivially redundant, it was relatable and tactile.

But then you have to glance at the thing every few minutes to ensure it didn’t run out