iOS 7 beta 4 fingerprint scanner

Apple's upcoming iPhone 5S will feature a fingerprint scanner, according to iOS 7. See also: Live coverage of Apple 2013 iPhone event from Cupertino, California.

iOS 7 beta 4 has strongly suggested that rumours of a fingerprint scanner on the new iPhone are true. The leaked software contains a folder called 'BiometricKitUI' and code which talks about the home button recognising a fingerprint. See also: iPhone 5S price in the UK.

It says: "image.label.left.hand_fingerprint.image"

"image.label.right.hand_fingerprint.status"

"Photo of a person holding an iPhone with their left hand while touching the Home button with their thumb"

"A fingerprint that changes colour during the setup process."

"iPhoto of a person holding an iPhone with their right hand while touching the Home button with their thumb. Recognition is complete."

Apple spent $356 million on security firm AuthenTec back in July 2012 and rumours of a fingerprint scanner have been doing the rounds ever since. At the time, AuthenTec said it has shipped more than 100 million fingerprint sensors for integration in portable electronics including over 15 million mobile phones.

9to5mac reports that a source familiar with the development of the next iPhone said the user interface for the fingerprint scanning system has been complete. They also confirmed the scanner would be used mostly for unlocking the phone, but there are many more possibilities.

If Apple makes an API available to developers then the fingerprint scanner would no doubt be used in all sorts of ways. It could also make its way onto new iPad models (the iPad 5 and iPad mini 2) and we don't see why it couldn't be well used on MacBooks, too.

The iPhone 5S is expected to be announced in September alongside the budget iPhone 5C, not the iPhone 6

(See also: iPhone 5C vs iPhone 5S comparison review: what's the difference between iPhone 5C and iPhone 5S?)

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