The second part in a series of beginner tutorials on integrating physical devices with the IOTA protocol. Introduction This is the second part in a series of beginner tutorials where we explore integrating physical devices with the IOTA protocol. In this tutorial we are basically recreating the use-case from the first tutorial. This time however, instead of having our relay module hard wired to a Raspberry PI, we will use a low cost WiFi module for signaling the relay. If you haven’t read the first tutorial in this series, you should read it before continuing as it reflects on the same basic use-case we are trying to recreate in this second tutorial. The Use Case Now that our forward leaning hotel owner has his new IOTA powered refrigerator payment system installed and working as described in the first tutorial, he start noticing some issues that make the solution less than ideal. First of all, having....