I know assembling things is half the fun, but if you just want a universal ESP32 device with screen and buttons, I recommend M5stack. Cheap, programmable, uniquitous.

They are great. I have actually built my own pomodoro timer using a M5Stack Core2, maybe I should publish the code. It's a lot simpler than this one.

Update: here it is https://github.com/robertolupi/augmented-awareness/tree/main...