Find out more details after the break.
The patent application describes several ways of identifying an unauthorized user, including voice analysis, facial recognition, heartbeat analysis, or hacking attempts. If an unauthorized user is detected, the iOS device could lock completely, wipe itself clean, log keystrokes, phone calls, or other activity, snap a photo of the user, or even send its exact location via GPS.
This kind of technology would be helpful for anyone concerned about the security of their data, not to mention helpful for recovering lost or stolen devices. Here's hoping it's implemented soon!