Systems and methods are presented herein for creating and using a multi-function device that allows a user to transform the device into the desired feature-set form which permit access to that feature’s functions, without a need for a user to traverse a series of interface menus to get to the desired functionality. The power supply apparatus includes two power suppliers coupled in parallel so as to simultaneously supply the electric power required by an electronic product in operation. The coil provides increased therapeutic benefit to a wearer.