Apple has submitted a patent application for using the iPhone's (or iPad's) Touch ID module, camera, and other sensors to grab information about whoever is using the device in the event that it is stolen.
The patent is called "biometric capture for unauthorized user identification," (spotted by AppleInsider) and covers how an iOS device could be turned into a surveillance device capable of capturing, storing, and even transmitting information on the person using it following the receipt of a signal to do so, or after a number of unauthorized use attempts have been made.
That information could be fingerprints, photos, video, and audio, as well as other undisclosed forensic information (perhaps location information and whether the device is moving or not).
Apple also takes this a step further, claiming "a captured fingerprint may be compared to a database containing fingerprints of known users (such as fingerprints of all users of a cellular service network that have been captured by the cellular service network)."
We're now deep into Big Brother territory, and at a point where some users would undoubtedly feel uncomfortable.
It's important to bear in mind that Apple files a lot of patent applications, and many never see the light of day in products. This could very well fall into that category.