Caution: knock-on unlock codes are dangerous for your smartphone

According to researchers at the New Jersey Institute of Technology, smartphone owners who use Knock Codes to unlock them can easily become victims of intruders.

Knock codes allow phone users to choose patterns to tap on the lock screen. In 2014, this unlocking method was popularized by LG. It is currently used by about 700, 000 people in the US alone, to which should be added the million users who have downloaded clone apps for Android devices around the world.

Knock codes typically present users with a 2 x 2 grid that they must tap with their finger in the correct sequence to unlock the phone. As a rule, you need to make six to ten taps.

In a study involving 351 volunteers, the researchers found that 65% of them began to "knock" in the upper left corner, then, usually moving to the next upper corner. Apparently, this pattern should be attributed to the habit of reading from left to right. The three most popular knock codes are shown in the figure above. They also found that increasing the mesh size did not help. Instead, users preferred to choose shorter codes.

Research has shown that knock codes are difficult to remember. About 1 in 10 participants forgot their code by the end of the study, even though it lasted only five minutes. In addition, it took an average of 5 seconds to enter such a code to unlock the display, compared to entering a PIN code, which usually takes 4.5 seconds, and entering a pattern key, which requires only 3 seconds.

According to researchers, developers need to create a function that will block "light" codes and recommend users to choose more reliable ones.