Abstract: A device, for monitoring the status of a user in an environment, includes a mobile module intended to be worn by the user. The mobile module includes an activity sensor and a processing unit. The processing unit is for establishing a status signal from an activity signal generated by the activity sensor. The device also includes beacons distributed in the environment. The beacons are configured to send a transmission signal to the mobile module via a short-range wireless connection. The processing unit is configured to establish a position signal as a function of at least one distance between the mobile module and a beacon. The transmission unit is configured to transmit the status signal and the position signal to a central unit.

Abstract: There is provided a computer-implemented method of selectively communicating with mobile devices. At each of a plurality of mobile devices, a travel mode between a plurality of locations is determined in dependence on one or both of: one or more sensors associated with each respective mobile device, and wireless location signals received at the mobile device. At each mobile device, at least some of the plurality of locations are selected as significant locations associated with a user of the respective mobile device. Each significant location is a location at which the user resides for extended durations of time. Each mobile device communicates to a server computer an identifier associated with each mobile device, a generalised identifier associated with each significant location and an indication of the travel mode to the significant location.