A photo of an alleged home button part for the iPhone 5S has leaked online, perhaps giving us a first look at the reported fingerprint scanner that will accompany the handset. Leaked by publication NoWhereElse, a flex cable is shown featuring a "mysterious square element" that may power the fingerprint scanning function.

This leak doesn't set fingerprint scanning in stone for the iPhone 5S, but it does add a bit of hope. The part combined with references to a fingerprint scanner that have shown up in developer beta of iOS 7 may give us an idea of what main feature Apple plans to market around the iPhone 5S. 

So why would you need a fingerprint sensor on a smartphone anyway? Well, it's actually more useful than you'd think, making for a great safeguard to unlock the device (rather than slide-to-unlock) and as a way to make purchases from iTunes more securely.

Of course, parts are constantly floating around China, so it's not clear if this is the real deal. We've seen an abundance of leaks for the plastic iPhone Apple is planning, along with case leaks for the iPhone 5. It is a bit odd that this is the first time we've seen anything for the fingerprint scanner. Either Apple and supplies have kept a tight lid on the parts, or you know, it just isn't happening. Though the part contains an identifier of 821-2092-01, on-a par with Apple's usual numbering scheme for parts.

Luckily, Apple has made official its 10 September media event at which it plans to introduce the new handset. Pocket-lint will be live from the event to bring you the latest - fingerprint scanner or no fingerprint scanner.