But now that millions of iOS and Android phones can become portals to any world an app developer dreams up, what's a Cupertino company to do next?
Dissect frogs, apparently.
Froggipedia is one of a host of new ARKit apps that Apple just announced, and it does exactly what you'd expect -- use the Apple Pencil stylus to peel the skin off a virtual frog. It's a little less gruesome, and presumably fewer real frogs have to die.
(Some CNET editors aren't convinced the experience would be as valuable, though.)
There's also Free Rivers, an ARKit app from the World Wildlife Fund that shows students the environmental impact of, say, building a dam on a river, and Boulevard AR, which lets students hang art on the walls of their real-life classroom. And they'll be able to program cartoony 3D animated characters and place them in the real world with the newly ARKit-enabled Swift Playgrounds.
The news was announced at an unusual Apple event at the Lane Tech High School in Chicago, where the company has just unveiled a new $329 iPad ($299 for schools) to help re-establish itself in the classroom. The iPad hasn't been doing particularly great, seeing years of sales declines before finally perking up over the holidays. Part of the reason: Competition from Google's Chromebooks, which have proven popular with students because of their low prices.
Would you buy your student an iPad to save a frog?
Froggipedia uses ARKit to make a virtual frog look like it's there in the room with you.
Apple's ARKit has some technical improvements under the hood, too. Originally, ARKit apps could only detect flat surfaces like floors and tables -- but in January, the company announced that ARKit 1.5 would work with vertical surfaces too, which will probably come in handy when you try to use Boulevard AR to hang paintings on the walls.
The upcoming software can also recognize some posters and art that might already be on your real-world walls: When CNET's Shara Tibken tried pointing an iPhone at a poster of a lunar lander in an early ARKit 1.5 demo, she was rewarded with an interactive video of the Apollo 11 moon landing.
The ARKit 1.5 update is just one piece of iOS 11.3, which should arrive on iPhones and iPads soon. The new $329 iPad might run ARKit apps better than some -- while its A10 Fusion processor isn't the latest and greatest Apple has to offer, it should be faster than the A9X in the previous $329 model.
Here's a list of all the iPhones and iPads that work with Apple's ARKit apps.