An electronic system includes a first wireless transceiving module having a device identification code and a portable device. The portable device may include a second wireless transceiving module, and a processor. The second wireless transceiving module obtains the device identification code from the first wireless transceiving module. When the second wireless transceiving module obtains the device identification code from the first wireless transceiving module, the processor checks whether the device identification code matches to a pre-built identification code; and when the device identification code matches to the pre-built identification code, the portable device automatically determines a position of the portable device, and displays a map related to the position of the portable device in a display.