Abstract: A multi-functional personal security device includes a housing for wear by a user. The housing contains a position module, a communications module, a smart switch, and first, second, and third security modules. The position module determines a geo-position of the housing. The communications module detects a cellular device. The security modules individually respond to activation of the smart switch to provide respective security functions. Switch activation occurs in response to a pressing sequence of a button and/or voice commands, which may activate the first security function only when the cellular device is present. Activation of the smart switch in response to a second input sequence activates the second and third security functions, e.g., a strobe and audible alarm. Panic, Silent Panic, Countdown, and Tracking Modes may be selectively enabled.