The biggest thing to watch for during Apple’s upcoming launch of the iPhone 5S will be whether the new device’s home button has a fingerprint sensor that can authenticate users and be used to confirm mobile payments. French website has published a leaked photo purportedly showing the iPhone 5S’s home button flex cable that features a much more complicated design than the home button flex cable used in the iPhone 5. In particular, notes that the purported new flex cable features a “mysterious square element” that’s placed fairly close to the home button and that may be part of the new device’s fingerprint scanning functionality.

Rumors about a fingerprint scanner on the iPhone 5S have been around for months and references to a biometric fingerprint sensor have shown up in older betas for iOS 7. We’ll know for sure whether Apple has actually incorporated this feature into its next device when the company unveils it next week.’s leaked picture of the home button flex cable follows below.