An electronic device that provides a drawing function according to a touch input, the electronic device comprising: a touch screen configured to: receive the touch input from a user, and display an object based on the touch input; and a control unit configured to: determine an object having a shape corresponding to a trajectory of the touch input; determine whether a previously generated object is present in a position associated with the received touch input; modify the previously generated object based on the determined object when the previously generated object is present; generate the determined object when the previously generated object is absent; wherein modifying the previously generated object comprises the control unit being configured to: determine whether a low order object corresponding to the previously generated object existing in the position in which the touch input is received is a basic object when the low order object is the basic object, in dependence on user input, either convert the low order object into a complex object based on the shape of the basic object or generate the determined object; and when the low order object is not the basic object, edit the low order object based on the determined object. a touch screen configured to: receive the touch input from a user, and display an object based on the touch input; and receive the touch input from a user, and display an object based on the touch input; and a control unit configured to: determine an object having a shape corresponding to a trajectory of the touch input; determine whether a previously generated object is present in a position associated with the received touch input; modify the previously generated object based on the determined object when the previously generated object is present; generate the determined object when the previously generated object is absent; wherein modifying the previously generated object comprises the control unit being configured to: determine whether a low order object corresponding to the previously generated object existing in the position in which the touch input is received is a basic object when the low order object is the basic object, in dependence on user input, either convert the low order object into a complex object based on the shape of the basic object or generate the determined object; and when the low order object is not the basic object, edit the low order object based on the determined object. determine whether a previously generated object is present in a position associated with the received touch input; modify the previously generated object based on the determined object when the previously generated object is present; generate the determined object when the previously generated object is absent; wherein modifying the previously generated object comprises the control unit being configured to: determine whether a low order object corresponding to the previously generated object existing in the position in which the touch input is received is a basic object when the low order object is the basic object, in dependence on user input, either convert the low order object into a complex object based on the shape of the basic object or generate the determined object; and when the low order object is not the basic object, edit the low order object based on the determined object. determine whether a low order object corresponding to the previously generated object existing in the position in which the touch input is received is a basic object when the low order object is the basic object, in dependence on user input, either convert the low order object into a complex object based on the shape of the basic object or generate the determined object; and when the low order object is not the basic object, edit the low order object based on the determined object.