TapLock: Exploit finger tap events for enhancing attack resilience of smartphone passwords

In this paper, we present TapLock as a smartphone password system that exploits the finger tap events on capacitive touch screens for increasing the password´s resilience to shoulder-surfing attacks (where the password input by a user can be easily observed by a bystander over the user´s shoulder). TapLock captures the size and the axis length of the finger touch area on the phone screen for creating a password, which cannot be easily observed by a shoulder surfer. Our user study shows that TapLock has several advantages over existing smartphone password systems, including its strong attack resilience, small authentication delay, and haptic input feedback that improves the usability.