Fingerprint Reader
(Fingerprint Scanner)
A hardware sensor that can quickly read a person's unique pattern of ridges on their fingertip, to verify that person's identity. This is a type of biometric security.
It can be used in place of a password to unlock a phone, unlock certain content or services, or confirm a financial transaction.
Fingerprint readers in phones come in several different types:
Some sensors are thin strips that read only part of a fingertip with a single touch, but enough to confirm the fingerprint with confidence. These are commonly integrated into the power/lock button on the side of a phone. (shown)
A fingerprint reader can also be integrated directly into (or layered under) the display of a phone. The sensor area will typically be centered in the lower half of the phone's display. Some of these read the fingerprint optically, while others use ultrasonic technology. Ultrasonic is sometimes considered more reliable, but it only found in higher-end phones.
Older smartphones had larger, more obvious sensors, like a fingertip-size pad on the back, that would scan the whole fingerprint at once upon being touched.
Going back further, some of the first fingerprint sensors in phones consisted of a thin strip that the user actively swiped their fingertip over.
Last updated Apr 24, 2026 by Rich Brome
Editor in Chief Rich became fascinated with cell phones in 1999, creating mobile web sites for phones with tiny black-and-white displays and obsessing over new phone models. Realizing a need for better info about phones, he started Phone Scoop in 2001, and has been helming the site ever since. Rich has spent two decades researching and covering every detail of the phone industry, traveling the world to tour factories, interview CEOs, and get every last spec and photo Phone Scoop readers have come to expect. As an industry veteran, Rich is a respected voice on phone technology of the past, present, and future.
