Since the company's standoff with the FBI, encryption tech has become sexy–in a very nerdy sort of way. Apple is adding to its large collection of encryption patents with new encryption tech that allows users to change an account password on one device and have it recognized by all their other devices. Ordinarily they'd have to type in the old password, then the new one, on a new device. Multiple encryption keys are generated in the process, the patent says.
And here's the picture the inventors helpfully included with the patent application, originally dated May 30, 2014.