We are happy to see Christian Mézes return and speak about Arduino:
Data acquisition and data processing with Arduino and Xojo
Arduino is an easy-to-use and inexpensive open-source electronics platform. With Arduino boards you can easily read sensor data and turn the data into an output. You can control the board by sending a set of instructions to the microcontroller on the board. While the Arduino boards bring their own programming environment, I will show you some interesting examples where we use Xojo to send commands to the board and to acquire/process data from the board.