System, device, and method of detecting identity of a user of an electronic device

A method for confirming identity of a user of a smartphone, the method comprising:

• receiving touch data from a touch-screen of the smartphone;
• receiving acceleration data from an accelerometer of the smartphone;
• correlating between the touch data and the acceleration data;
• based on the correlating, generating a user-specific trait indicative of said user of said smartphone;
• storing, either locally within said smartphone or on a remote server, a reference value of the user-specific trait, indicative of said user of said smartphone;
• in a subsequent usage session of the smartphone, generating and storing a current value of the user-specific trait correlating between touch data and acceleration data;
• and
• based on a comparison process between (A) the current value of the user-specific trait that was generated, and (B) the reference value of the user-specific trait that was previously generated, determining whether or not a current user of the smartphone is an authorized user of the smartphone.