Touch ID
Apple patent explains how a thief's fingerprint could be captured by a stolen iPhone Reuters

Apple is developing a way to use the cameras and fingerprint reader of an iPhone to help identify anyone who steals it. A patent recently updated by the California company details the changes, which include the use of fingerprints for the first time.

Apple explains how a "trigger condition" would cause the iPhone or iPad to start gathering information on who the thief might be. This includes taking their picture with the front-facing camera and capturing their fingerprint with the TouchID system on its home button.

Such triggers could include a thief trying to gain access to the iPhone via a third-party device, or attempting to bypass the phone's security features, like the passcode entry screen.

First filed in June 2012 and updated on 25 August 2016, the patent states how the theoretical system could gather information such as "one or more fingerprints, one or more images of a current user, audio of the environment of the computing device, forensic interface use information, and so on". This data would then be stored and provided to the authorities "for identification of one or more unauthorised users."

Capturing photos, video and audio of the thief and their surroundings – plus the phone's GPS location – is relatively simple, even at the system level, in other words, in the background and without the user being aware of it happening.

The data could be sent to the phone owner's iCloud account, accessed remotely via a computer or another iOS device. Some third-party apps already exist to perform this function, but Apple's proposal goes a step further by suggesting the data could be cross-checked against online databases, as a way of catching repeat offenders.

Making use of fingerprint data will be more difficult. Currently, Apple claims fingerprints saved to an iOS device are stored in a 'secure enclave' of the processor and not uploaded to Apple's servers. If a stolen iPhone is to record the thief's fingerprints, then these will need to be uploaded online, otherwise they could only be accessed once the device has been found.

Users logging into iCloud to try and locate a stolen iPhone could potentially allow the phone at this stage to upload print scans to Apple and the authorities every time the Home button is pressed, but the patent does not expand on this. The system would also need to tread carefully from both a legal and ethical point of view, given Apple's repeated defence of user privacy.

As always with technology patents, the features discussed here might never arrive on a future iPhone, but it is still interesting to see what companies like Apple are working on, sometimes years before it goes on sale.