Update counter from arduino to MIT APP inventor label

Hello all. I'm brand new to C++, brand new to arduino, and brand new to MIT App inventor.

I wrote an arduino sketch that blinks a light and counts the blinks and writes the counter into the arduino serial monitor.
I want to take that counter and send it to a label on my MIT app inventor app.
Is a label the best option to use, and how would I go about doing this? I don't know what blocks to use.