As expected, on Wednesday Sept. 9, Apple unveiled the new iPhone 6s and iPhone 6s Plus and, as expected, it features the variable-pressure sensitivity known as "Force Touch" to most, until today.

Now we know Apple's calling the technology it first introduced on the Watch and 2015 Macbook Pro"3D Touch" after porting it to the iPhone. And though the feature itself was long-expected, the far-reaching implications for how it may revolutionize the way you navigate your smartphone could be unpredictable.

What 3D Touch Is

3D Touch, as the name aptly implies, adds a new dimension of interaction between you and your touchscreen device; In this case, the new iPhone 6s and iPhone 6s Plus (only, so far).

When you take hold of an iPhone 6s, you'll have more options for input than just the normal gestures like swipe and click. 3D Touch can tell that you're pressing harder on the screen, and brings up new ways of navigating between tasks, and faster shortcuts within the home screen and apps.

There are two major actions with 3D Touch: the "pop" and "peek." Peek lets you click on app icons from the home screen to bring up a contextual menu, allowing you to quickly access features like bringing up directions home on Maps or getting a preview of a message on Mail.

"Pop," the hardest press, gives users the ability to, well, pop up content like videos and photos quickly on the screen, without actually having an app take over the iPhone.

Third-party apps like Dropbox and WeChat already support 3D Touch's "peek" and "pop" with unique shortcuts of their own, and more developers will obviously take advantage of that going forward. Games are taking advantage too, with WarHammer, for example, creating a zoom function for when you press harder on the screen.

Apple's Phil Schiller demonstrated the new 3D Touch features, including the ability to seamlessly navigate between open apps on the app switcher with just a little more finger pressure on the screen, rather than double-clicking the home button.

Ready to Leave Home?

In addition to the new 3D Touch feature, thanks to new features built into the A9/M9 coprocessors in the iPhone 6s and iPhone 6s Plus, Siri now works completely touch-free. Hence the event's name, "Hey Siri!"

Those two factors combined -- and the inevitable improvements and expansions in functionality, and the inevitable surprising new features that come from creative developers taking advantage of this entirely new (excluding Huawei's attempt) input system -- make the homely old physical Home button seem obsolete.

At the very least, it seems to be heading for obsolescence as a physical "button," once centrally important to the operation of iDevices.

Maybe it will remain, but only as a place for Touch ID fingerprint scanning -- and a vestigial reminder of what iPhones were like back when touchscreens were one-dimensional.