This robot, built out of LEGO bricks and a Raspberry Pi, brute-forced an iPhone for PIN codes. image provided with the permission of Maximilian Golla ...

Video There's nothing particularly difficult about cracking a smartphone's four-digit PIN code. All it takes is a pair of thumbs and enough persistence to try all 10,000 combinations. But hackers ...

The PIN codes used to protect smartphones offer a useful line of defense against criminals - unless, that is, your device falls into the hands of the robot R2B2.

These security researchers built a LEGO robot with a Raspberry Pi brain to help find out. iOS has a built-in blacklist of certain four-digit and six-digit PIN codes.