The black box of the plane is probably the most crucial piece of equipment should the plane crash. It basically contains all the information and logs about the plane and its equipment right up until the crash, so that when forensics attempt to find out what went wrong, and when it went wrong, they can just refer to the black box. A patent recently published by the USPTO shows that Apple may have something similar planned for future iPhones.
The patent revealed that an RFID chip would be used to act as a black box of sorts, as the patent drawing the picture above suggests, a “trigger” event would be logged on the RFID chip which can then be read by an external reader, even if the device or parts of its hardware is no longer operational.
For example when your phone has been exposed to water, i.e. dropping it in the pool, got wet in the rain, etc, the best thing to do is to turn the device off and let it dry. Through the passive RFID circuitry, if you were to bring it to an Apple store to get it fixed, the person in charge could then use NFC technology to convey data or a message, indicating that it has been damaged due to immersion/exposure to water. This would aid in helping diagnose problems with the iPhone in a quicker manner, and hopefully cut down on repair time.