All the way back in February of this year, Apple's iPhone business alone surpassed the size of Microsoft's entire business, reaching nearly $25 billion in quarterly revenue versus Microsoft's ~$20 billion.

Since February, Apple's iPhone business has only grown, widening this gap.

Here's the outdated chart from February:

Remarkable isn't it?

Here's what's more remarkable yet: At this very moment, Apple is working on technology that, if successfully developed, will cannibalize and ultimately destroy that iPhone business.

We have two pieces of evidence.

The first is that Apple has established a pattern.

Unlike most companies, Apple has a remarkable ability to predict the kinds of gadgets that will undercut the gadgets it sells, and then build these new gadgets better than anyone else could.

The best example of this is the iPad, which is actively disrupting Apple's own Mac business.

During Business Insider's Ignition Conference last week, top Apple analyst Gene Munster of Piper Jaffray talked about Apple's tendency to cannibalize its own businesses and predicted that it would continue to do so.

He speculated that Apple is working on consumer robotics, wearable computers, 3D printing, consumable computers, and automated technology.

He showed everyone this chart, which visualizes Apple's pattern:

Here's the other reason it's safe to assume Apple is quietly working on the destruction of its most massive business, the iPhone.

Just like Google and Microsoft, Apple is working on computerized glasses.

Computerized glasses, are, at the moment, the technology that is most likely to bring the smartphone era to an end.

They fit into an obvious pattern, where computers have been getting smaller and closer to our faces since their very beginning.

First they were in big rooms, then they sat on desktops, then they sat on our laps, and now they're in our palms. Next they'll be on our faces.

We have the rough schematics of Apple's project.

They've been publicly available on the US Patent Office's website since this summer, when they were noticed by several Apple-watching websites.

In the patent filing, Apple calls the gadget a "head-mounted display" or "HMD."

The filing is authored by Tony Fadell, designer of the iPod, and John Tang. Fadell is no longer at Apple, but Tang is.

Some highlights from the description:

An HMD is "a display device that a person wears on the head in order to have video information directly displayed in front of the eyes."

"The optics are typically embedded in a helmet, glasses, or a visor, which a user can wear."

"HMDs can be used to view a see-through image imposed upon a real world view, thereby creating what is typically referred to as an augmented reality."

Apple says HMDs can be used…

To "display relevant tactical information, such as maps or thermal imaging data."

To "provide stereoscopic views of CAD schematics, simulations or remote sensing applications."

For "gaming and entertainment applications."

A gadget that features applications for maps, games, and a million other uses? Sounds familiar.

Here's an illustration from the patent filing: