A "BiometricKitUI" folder within the software code indicates a biometric sensor will be embedded into the phone's Home button.
The software code also mentions "a fingerprint that changes color during the setup process" and refers to someone specifically "touching the Home button with their thumb."
The user interface for the fingerprint scanning system is complete, a source told the 9to5 Mac website, and the technology is apparently intended to help unlock the phone or secure user data.
Rumors of biometric technology in the next generation iPhone have been swirling every since Apple acquired fingerprint sensor firm AuthenTec for $356 million in July 2012.
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