A handheld device with switchable signal receiving modes includes a telescopic antenna, a telecommunication transceiver module, a satellite signal module, and a switch circuit. The housing has a housing rim defining an opening to the cavity. Each of the piezoelectric rings is interposed between two adjacent filler rings. A transparent tapered tip is positioned on the distal end of the endoscopic dissection shaft. A display unit displays the address of the external device in a first display form which is different from a display form of other addresses in a case where the determination unit determines that the address of the external device is included in the address book and when the address book is displayed.