Disclosed herein is a touch screen apparatus including a touch screen having a geomagnetic sensing function and a near-field communication (NFC) function and configured to calculate touched coordinates using a touch input signal when the touch input signal is generated as a location on a touch panel is touched by a touch screen electronic pen after the touch screen is powered on; the touch screen electronic pen having an NFC function, and configured to take notes on the touch panel according to a user's manipulation and transmit the touched coordinates calculated by the touch screen to a main central processor; and the main central processor having an NFC function, and configured to receive the touched coordinates from the touch screen electronic pen and output characters corresponding to the touched coordinates onto the touch panel.