The same principle of door unlocking is also used for garage doors.
We often hear of disrupters, which block the signal when you lock a vehicle and prevent them from being locked. When an owner moves away from the car, a thief simply enters the car. The men in blue always warn us to always check if the car is really locked. But a cheap device of a hacker Samy Kamkar – he spent only 30 Euros for making it – has solved this problem. Namely, when an owner presses the key for locking doors for the first time, RollJam will block the key signal and save the code for unlocking vehicle (every code can be used only once!).
If the user will notice this and will press the unlock key for the second time, the device will have two codes: one to unlock the door, whereas the other will be saved by the device to enable the evildoer to unlock the door. Kamkar said he is doing this to warn of deficiencies in the system.