Software update is one of the major parts of the modern big IoT Solutions. This is probably also one of the most critical and sensitive parts in IoT Solutions. For the big IoT Systems we need to solve different cases firmware and business applications update. We need to have scalable and HA repository, but also need to have a device pooling based on campaign concept. It is needed to update software packages, but also often to provision containerized business applications. This talk is about the real-life cases and best practices when need to design and implement device software like general concepts and specific implementations using Microsoft Azure.