A deactivator device for a mobile Point of Sale (mPOS) systems includes a pair of spaced apart, fixed position electromagnets positioned and configured such that magnetic fields generated by the electromagnets aid one another to form a combined magnetic field; a battery; a capacitor; and an electronics assembly including a microcontroller configured to control storage of energy from the battery in the capacitor and to selectively provide a deactivation or activation pulse from the capacitor to the electromagnets. The components may be positioned in a housing configured for attachment to a mPOS mobile device.