With Arduino devices, it is compatible with any board. The only limitation that it presents is that you cannot load code from your smartphone to the Arduino board (as that would require specifying the Arduino version).
It can be used to send and receive data from the USB connection (the "serial").
In this video you can see a small demo (made with Thunkable, but doesn't matter), and see the blocks needed around timestamp 0:34:
And here is the respective Instructables:
Note it talks about an "extension", but its behaviour is like the Serial component.