I recently discovered that two fingers can be used to make one touchID. I have just tried 3 different fingers and my IPhone gives access to each of the digits. This means that the five touchID slots can be used to store fifteen different fingerprints, or at least 10 fingers and five toes! I would be interested in reading how many different fingerprint you can register for each of the touchId slots. I would also love to know how it works as I kind of thought it was a little more secure than that.