Abstract: A device, system and method for measuring physical activity, especially applicable for monitoring and inspiring physical exercise of e.g. children and adolescents. The prior art devices appear to lack the inspiring effect especially when children and adolescents are concerned. The object is achieved with a solution in which a portable exercise measurement device of a user has elements for transferring data with another measurement device and/or with a location indicating device and/or with another mobile device. The data transfer is based on short range communication, such as Bluetooth, Near Field Communication (NFC) or Radio Frequency Identification Device (RFID) technology. The device facilitates interactive playing which includes physical exercise.