Fingerprint or PIN?

Pros and cons of cell phone locking methods

Any smartphone can be unlocked using various methods. Besides the classic PIN and the wiped pattern, the display can also be unlocked via fingerprint. Each encryption technique has advantages and disadvantages, which are explained in more detail here.

Pros and cons of the PIN

The PIN is a classic method that has long been used to protect devices or cards. It is usually a combination of numbers that the user sets and enters himself to unlock his smartphone. The PIN can be between four and 10 digits long, depending on the device and the setting.

The PIN has the advantage that it is not bound to the body. This means that it cannot be stolen as easily as a fingerprint. In addition, the PIN can be changed at any time if it has been spied out by others or if it has been forgotten.

However, the PIN also has disadvantages. On the one hand, you have to remember the numbers and enter them every time, which is somewhat cumbersome and time-consuming. Secondly, the PIN can be guessed or spied out, for example by observation or fingerprints left on the display. If you still want to use this method, you should never use combinations like your own date of birth or number sequences like 1234.

Wipe pattern? - better not!

Pattern wiping is a popular method to unlock a smartphone's display. It is simple and fast, but unfortunately very insecure. A study by Lancaster University came to the conclusion that 95 percent of all patterns can be cracked within five minutes. The reason: Many users choose simple and short patterns that often represent letters like the "M," the "V" or the "Z." These patterns are predictable and easy to crack.

Furthermore, this unlocking technique leaves traces on the display. Wiping the display with a finger leaves grease stains that can reveal the pattern. An unauthorized person with criminal energy would have an easy time exposing the traces with the naked eye or a special camera. To avoid this, the display would have to be wiped after every use, which is very inconvenient.

Fingerprint - what are the pros and cons?

The fingerprint is a biometric feature that makes each person unique. It cannot be easily forged or copied like a PIN. Many modern smartphones have an integrated fingerprint sensor that recognizes the user's fingerprint and unlocks the device. This is very convenient and quick, because you don't have to remember or enter any numbers or letters.

However, some arguments speak against this unlocking method. For one, the sensor can get dirty or damaged, which makes recognition difficult or impossible. Secondly, the fingerprint can be accessed by third parties. We leave fingerprints everywhere: on the door handle, on cups, on keyboards, on pieces of furniture, on cell phone screens, etc. Consequently, there are countless places that hackers can use to get hold of the supposedly secure "password".

Forced unlock by fingerprint

Those who use their own fingerprint as a security method must be aware that the unlocking of the phone screen can be forced. All it takes is someone to get the user to press their fingers on the screen and the biometric lock proves ineffective.

Even the police are entitled to take fingerprints in order to unlock the smartphone. This was decided by the Ravensburg Regional Court in its ruling dated February 14, 2023 - 2 Qs 9/23. The reason given for the ruling was that the "fundamental right to informal self-determination must take second place to the public interest in the effective administration of criminal justice". Important: If the cell phone is secured with a PIN or unlock pattern, the person concerned does not have to disclose these even during a police investigation.

Conclusion: Both fingerprint and PIN have advantages and disadvantages as unlocking methods for the smartphone. Which method is more secure depends on various factors such as the device type, user behavior and the individual threat scenario.