StackyPi is a compact and advanced board that is designed with the RP2040 Micro-controller, which provides one set of 2x20 pin headers on which you can connect Raspberry Pi HATs. It means that one can plug HAT designed for Raspberry Pi and run it via the Pico Zero RP2040 that would make the user perform the advanced functions on it.
StackyPi consists of standard Raspberry Pi 40 pins on its board for Raspberry Pi HAT. One can plug Raspberry Pi HAT by directly putting it on the StackyPi that has the power pins for the connection. StackyPi is a board on which, clear and descriptive pin labels make the process easier for the user.