An apparatus and method for sensing body temperature and wirelessly communicating measured data to at least one electronic device. The device includes a sensor device having a housing base, a housing cover releasably mountable on the housing base, and components for sensing body temperature and wirelessly communicating the measured temperature, including a temperature sensor, a power supply, a microprocessor, and a transmitter and receiver. The electronic device can include an application that communicates with the sensor device and provides a user interface.