An external device of a mobile phone for inputting and permuting original script comprises a handwriting sensing device for sensing handwriting script and generating script coordinates or displacement data; a transmission interface for transmitting the script coordinates or displacement data to a mobile phone; a means for compressing or expansion the scripts from the mobile phone into figure lattices of the same height; and permuting the figure lattices on a display screen of the mobile phone in order so as to form a drawing showing original scripts. Furthermore, a method is included, which comprises the steps of sensing handwriting script and generating script coordinates or displacement data; transferring the script coordinates or displacement data to a mobile phone; compressing or expansion the scripts from the mobile phone into figure lattices of the same height; and permuting the figure lattices on a display screen of the mobile phone.