Over the last few years, web services have evolved enormously, from archaic text-only websites where only the web master can upload and update content, to the most modern applications such as social networks with video calls and real-time video streaming where all users interact and create new content. All these advances in the way services are built and how we interact with them have been made possible by major technological improvements and contributions, such as the increasing speed of access networks, the evolution from desktop to laptop computers, the emergence of pocket devices such as smartphones and the development of even more powerful wireless access networks, such as the evolution of mobile telephony standards. Despite all this evolution, technology has not stagnated and continues to evolve to provide us new ways to build services and interact with virtual worlds. In recent years, new technologies have appeared, and these technologies have produced a paradigm shift in the relationship we will have with web-based services, and some companies are even talking about the beginning of a fully immersive metaverse. In this thesis we will analyze some of these technologies, such as blockchain networks, their possible social implications and we will develop an application based on this technology following a circular economy framework.Objectius de Desenvolupament Sostenible::9 - Indústria, Innovació i InfraestructuraObjectius de Desenvolupament Sostenible::10 - Reducció de les Desigualtat
