“Unlike Facebook or Instagram, Twitter's core experience isn't about photos. It's…” — Om Malik

The early entrants into the world of A.R., as with its cousin virtual reality, were disappointing: the phones were too weak, the networks were too slow, and the applications were too nerdy. But now the technological pieces are in place, and a whole generation - much of which is on Snapchat - has come to consider the camera almost a third arm.

The possibilities that come with thinking about the camera as a portal into the realm of information and services are attractive not only to Snap but also to every other big player in the tech world. Facebook, for instance, has slowly been enhancing the visual capabilities of its Messenger.

QR codes have always been a kind of half-measure, a useful but inelegant transitional technology; the ultimate goal is augmented reality.

Cameras can look down from on high and predict crop yields, traffic in Walmart parking lots, and travel patterns on Labor Day weekend. On the ground, they form the foundation of autonomous-driving systems.