An electromagnetic device includes a core and a coil in the space between a central section and an outer section of the core and spaced inwardly of an open side of the core such that the coil is completely recessed within the core. The all solid state battery of the present invention comprises a negative electrode layer, a positive electrode layer, and a solid electrolyte layer having a lithium ion conductivity. Functionality can be implemented to coordinate communications of collocated WLAN and WWAN devices to minimize interference between the WLAN device and the WWAN device.