The next revolution could be in software that is only possible with the power available in the iPhone X, that will be mainstream for other phones in a couple years.

I had an app called Vindigo on a Handspring Visor and later a Kyocera 6035 in the early 2000s that gave the location and mapped pretty much every restaurant, bar, and museum in New York long before maps were an obvious part of your phone.

I think the possibilities of AR are amazing, even though I don't think whatever the killer will be has been released yet.