These days everyone is walking around face down with a cell phone in hand. So, why not put some usable data on that cell phone display? Today, we will write a pair of Raspberry Pi 4B applications for a couple of GSM modules. Our first GSM application will target the Telit GL865-QUAD V3. Once we get the Telit application running, we will turn our attention to writing a similar application for the Quectel M95. Both applications will be tasked with communicating with my iPhone via SMS messaging.