Smart watches and associated systems and methods thereof for lock-screen management are disclosed. A smart watch includes a heart rate sensor, and a method for lock-screen management of the smart watch includes: reading, by the heart rate sensor, a heart rate determining based on the heart rate whether the smart watch has been taken off by the user, and if yes, stopping the heart rate sensor from working and entering by the smart watch a password-lock-screen mode. Thus, using the method according to the present disclosure can improve the information security on the smart watch.
