The problem with patterns
For her master's thesis, Marte Løge, a 2015 graduate of the Norwegian University of Science and Technology, analyzed 4,000 lock patterns. She found that over 77 percent of people start their pattern in one of the four corners, and 40 percent start in the top-left corner.
Just as worrisome, most people only used the minimum of four nodes or just five nodes for their pattern, which drops the possible combinations from the maximum of 140,704 to 1,624 and 7,152, respectively. That's still too many for a person to guess, but just like with the 4-digit PIN, there are some combinations people favor, and hackers will eventually figure them out.
A quick "L" or "Z" shape starting in the upper-left corner or an up-down snake pattern are very common, for example. Løge also found that 10 percent of her subjects spelled out a letter that had some significance to them, such as a spouse or child's first initial.
That means a hacker, especially if they know the victim, has a small but solid chance of guessing the pattern in not many tries. It's like the early days of computer passwords all over again.
If you're using a pattern on your gadget, what steps can you take to keep someone from guessing it?