A mobile data processing device, such as a portable computer, a tablet computer or a smartphone manufactured to comprise: - a defibrillation electronic circuit; - a battery intended to supply said defibrillation circuit; - a software programme to assist with use in order to enable the general public to use the defibrillator. The device comprises a medical diagnosis and monitoring unit comprising at least one sensor for monitoring a piece of physiological data of the user of the device.