In reality IoT solves the same simple problem for communication points as software architecture tries to solve for many years – distributed computing. Different nodes on difference machines try to communicate with each other as well different Devices and Microcomputers. This devices can report about their statuses and interact with the environment. The main focus of the talk is that C# could replace Java for small devices, e.g. Arduino and Raspberry Pi. The talk includes some insights and gotcha about building your own IoT device with C# and cellular connectivity.