HOW TO STOP A THIEF FROM USING YOUR SAMSUNG GALAXY NOTE 3 (REACTIVATION LOCK)
With the introduction of the iOS 7, Apple included an anti-theft feature called the Activation Lock which would prevent the would be thiefs from activating the device after it has been stolen (as long as the original owner has the device tied to an iTunes account/Apple ID and remotely locks the device).
Samsung has taken a play out of Apple's playbook with a Reactivation lock. The reactivation lock works with a Samsung account and prevents users from resetting the phone after it has been stolen, the original owner can remotely lock and wipe his details from the device after it has been stolen. One of the good things about the Reactivation lock is that even after the phone has been reset using the Android built-in factory reset feature, the Phone still prompts for the Samsung details that the device had on before it was reset.
To enable the Reactivation lock on your Samsung Galaxy Note 3, all you have to do is to click on The SETTINGS, GENERAL tab, SECURITY and check the REACTIVATION LOCK
You should check out the video below to see how the REACTIVATION LOCK feature works.
Video from SamsungHub