Our smartphones carry a lot of personal information. All of your text messages, emails, notes, apps, app data, music, pictures, and so much more are all on there. While it's a very great convenience to have all of these on your phone, it's also a major security risk if all of this data is easily accessible. The best way to prevent simple unauthorized access is by setting some sort of lock on your phone.
Two popular choices, especially on Android phones, are passwords and pattern locks. However, which one is the most secure to use? In order to answer that, we'll have to use our brains and some math.
Passwords are a bit harder to use than pattern locks because you actually have to type out your password. They are, however, still plenty easier than some desktop authentication methods available, such as multifactor authentication. But just how safe are they? In order to figure out how safe a method is, you'll have to look at the number of possibilities.
No method is completely safe if an unauthorized user knows your password or pattern, but if they don't know, they'll have to keep guessing. If there are more possibilities, the person will have to make more guesses, which makes it safer and more secure. In total, that's about 90 different possibilities with a US English keyboard. Each character can use all possible entries, so each character can be any of those 90 possibilities. In mathematical permutations, we have to multiply them together.
So for a 90 character password, 90*90*90*90*90= 5,904,900,000 . That's almost 6 million different passwords you can make if it's only 5 characters long! No one will manually try to type in 6 million different passwords in order to guess the right one. Of course, for each additional character in your password, you multiple that number by 90. So upgrading to just a 6 character password gives you 531,441,000,000 possibilities. That's a lot.
Pattern locks, however, are quite different. Although they look quite confusing and complex, they're actually not. In order to explain why not, we'll need to look at the maximum number of permutations. When you first start with your pattern, you have nine points to choose from. This will be our first factor. Let's take the choice which gives us the most amount of options: the middle point. From here, you can pick any of the eight others as your second point. This will be our second factor. Whatever point you picked will give you the number of available neighboring points. A corner point leaves only two options, while a side point gives you four — the two corners and the adjacent side points.
But lets ignore the fact that you may (or may not) have to pick a neighboring point. If you can go to whichever point you'd like next, you'll only have seven available options left as you can't pick a point twice — the reason why each factor's value is declining. This is our third factor.
The fourth and fifth factors would, ideally, be six and five. Therefore, under ideal conditions, the maximum amount of permutations you can get with a 5-point pattern is 9*8*7*6*5= 15,120 . Even if you went ahead and used a 6-point pattern, you'd only get a total of 60,480 permutations. Compared to what passwords offer, that's absolutely nothing.