Biometric security has arrived on the smartphone — again. For the first time since Motorola’s Atrix 4G arrived in 2011, a major US mobile device will carry a fingerprint scanner. The iPhone 5s’s new Touch ID sensor, embedded in the home button, will allow for faster and more secure logins, Apple said today at its event in Cupertino. The scanner, which uses technology Apple acquired last year when it bought security company AuthenTec for $356 million, will ship with the new iPhone on September 20th. It will not ship with the iPhone 5c.

Part of The Verge Live: Apple's 2013 iPhone event

The fingerprint scanner allows users to log in more quickly, Apple said, and will help prevent unauthorized access from someone who guessed or stole the owner’s pass code or phrase. It can also be used to make purchases in iTunes. The fingerprint is stored on the device and never backed up to the cloud, the company added.

The scanner is designed to address the fact that about half of iPhone customers don't bother setting up a passcode, Apple's Phil Schiller said on stage today.