A device comprising: a sensor means for deriving, on basis of one or more sensor signals that are descriptive of respective physical characteristics pertaining to a user, at least one measurement signal that is descriptive of a characteristic pertaining to the user; a communication means for wireless communication over a wireless link (102, 106); and a control means (115, 116, 117) for causing the device to perform at least the following: obtain, from said sensor means, first measurement data that comprises one or more values indicated by the at least one measurement signal and transferring the first measurement data to a server device over a first wireless link; receive, from the server device, device information that comprises at least a device identifier and access information for another device that is capable of providing second measurement data that is descriptive of one or more characteristics pertaining to the same user; in response to receiving said device information, detect presence of said another device and establish a second wireless link with said another device using said device information received from the server device; and receive the second measurement data from said another device via the second wireless link and transferring the second measurement data to the server device via the first wireless link. a sensor means for deriving, on basis of one or more sensor signals that are descriptive of respective physical characteristics pertaining to a user, at least one measurement signal that is descriptive of a characteristic pertaining to the user; a communication means for wireless communication over a wireless link (102, 106); and a control means (115, 116, 117) for causing the device to perform at least the following: obtain, from said sensor means, first measurement data that comprises one or more values indicated by the at least one measurement signal and transferring the first measurement data to a server device over a first wireless link; receive, from the server device, device information that comprises at least a device identifier and access information for another device that is capable of providing second measurement data that is descriptive of one or more characteristics pertaining to the same user; in response to receiving said device information, detect presence of said another device and establish a second wireless link with said another device using said device information received from the server device; and receive the second measurement data from said another device via the second wireless link and transferring the second measurement data to the server device via the first wireless link. obtain, from said sensor means, first measurement data that comprises one or more values indicated by the at least one measurement signal and transferring the first measurement data to a server device over a first wireless link; receive, from the server device, device information that comprises at least a device identifier and access information for another device that is capable of providing second measurement data that is descriptive of one or more characteristics pertaining to the same user; in response to receiving said device information, detect presence of said another device and establish a second wireless link with said another device using said device information received from the server device; and receive the second measurement data from said another device via the second wireless link and transferring the second measurement data to the server device via the first wireless link.