Electronic arrangement for single-source cross-platform media measurements, comprising a communication interface arranged to receive observation data having regard to and at least partly determined at a plurality of electronic, preferably personal, devices of a number of users, at least one user of said number being associated with multiple devices of said plurality, said multiple devices belonging to mutually different technological platforms including online platforms for providing media exposure and the multiple devices comprising a usage meter to observe selected events indicative of device usage comprising media exposure, wherein the usage meter of at least one of the multiple devices being further arranged to observe user exposure to media on one or more external offline media distribution platforms, and at least one of the multiple devices being arranged to transmit observation data comprising indications of the observations towards the arrangement, at least one electronic database arranged to store the received observation data and user profile data linking the users with associated electronic devices, and an analyzer functionally connected to said database and arranged to operate on the data therein to determine at least one data file indicative of user-level media exposure metrics incorporating metrics describing the at least one user's behavior including media exposure on multiple platforms, said platforms comprising one or more offline platforms, and multi-platform usage sessions involving two or more simultaneously or sequentially utilized platforms. Related electronic device and methods are presented.