An AR app that recognizes a book cover, then proceeds to wrap that book in its Amazon page.

Why on earth would we need that? First of all because it's weird. But it's also a recurring theme for me. My first attempt at connecting books and ebooks was barcode-based, but the targeted problem is the same: discovering books is a lot more fun when paper is involved. Reading them, at least for me, and 90.5 million ebook users, is more practical when you can carry your entire library with you always.

And who knows what other physical and digital counterparts we could discover just by glancing at their real-world manifestation? Maybe you could take on your "I'm buying a car" glasses, and all cars on the road that are for sale would get a giant price tag and an email form. Or how about spotting your Twitter followers in a crowded cafe? We tried that in the 2000s, and it was almost fun, but then our Nokia batteries drained.