The objective of this project is to devise a modular mobile positioning architecture that radically integrates opportunistic radio-localization signals. The vision is of a wireless mobile device that can pervasively position itself by integrating satellite navigation and network communications. We especially target areas such as the gray zone, where single technologies such as GPS fail. We aim to reach this goal addressing the following fundamental research questions: (i) how to fuse timing signals of satellite navigation with opportunistic signals inherent in WiFi and other radio communications (ii) how to (re-)configure the modular architecture, according to the dynamicity of both the services’ demand and location ecosystem. We propose to design and build experimental prototypes to assess our architecture in real-life use cases. Our work will be organized in two core topics: (a) introduce and assess algorithms and methodologies to blend timing signals of different radio technologies, subjected to diverse sources of noise, (b) study and implement techniques (partially) to outsource the computation of the position and the reconfiguration of the modular architecture to the network in order to optimize the mobile energy efficiency.