Electronic device and inputted signature processing method of electronic device

An electronic device comprising:

• a memory configured to store at least one registered handwritten signature as reference signature data;
• an input interface configured to receive a handwritten signature that is input;
• and
• a controller configured to:
• repeatedly register, as reference signature data, at least one handwritten signature input by a user input means as many times as a predetermined number of times, in the electronic device;
• determine a signature recognition rate of a user based on whether an authentication error is generated while a signature is input the predetermined number of times;
• adjust a permissible threshold to be lowered when the signature recognition rate of the user is lower than a predetermined value, wherein the permissible threshold is set according to a type of the user input means and a reference value to be satisfied for a signature authentication;
• and
• execute a process to compare the input handwritten signature data and the registered handwritten signature data when a handwritten signature data of the user is input by a user input means, to authenticate the input handwritten signature, and
• execute the authentication to satisfy the adjusted permissible threshold.