Abstract. Middleware platforms have become an essential part of the modern Internet of Things (IoT) and more recently Web of Things (WoT). These platforms provide the necessary tools for data storage, processing and visualization as well as for discovery, management, and interconnection of devices, which are used by manufacturers, system integrators and end users.In this paper we first present our view on the evolution of the Web and propose a new definition of Web 3.0 based on the number of content originators, which to the best of our knowledge hasn't been formalized in the same way before.We then give an overview of the existing IoT platforms, including our own solution, outlining technological trends on the one side and important concerns on the other. In the end, we discuss the possible direction towards the Web of Services as a potential way to solve one of the problems.