The handful of smartphones that existed back in 2007 were mostly fitted with QWERTY keyboards and tiny displays. There were a select few touting touchscreens, but they used resistive technology as opposed to the much more accurate and finger-friendly capacitive technology. Thanks to Apple and the iPhone, times have changed and capacitive touchscreens are now everywhere and on nearly every handheld device worldwide.

But how much longer will the touchscreen stand alone?

I was browsing the Internet just before going to sleep the other night and stumbled upon a headline on Pocket-lint reading, “The new gesture technology that could kill the touchscreen.” Obviously intrigued, I clicked the link. The story detailed a new gesture-based system developed by Qualcomm which could “spell the end of the touchscreen as we know it,” according to Stuart Miles of Pocket-lint.

The technology uses ultrasound through the phone's built-in microphone to judge where your hand is. You can flick through images, home screens, and do pretty much anything you can with a touchscreen with simple off-screen gestures. Think of it as a Kinect for your phone, but it uses ultrasound instead of a camera. Qualcomm is calling this the “digital sixth sense” and the technology should be incorporated in phones by the end of 2012.

Could this be the end of the touchscreen as we know it? I doubt it. But it's certainly useful, especially in something like mobile gaming; there wouldn't be big names like Texas Instruments and Qualcomm exploring the technology otherwise. Gestures would undoubtedly work great in conjunction with a touchscreen, but I can't see it totally replacing touch-based input. For one, gestures just simply are not as accurate as physically touching a display. And somehow I feel that ultrasound isn't exactly the best approach either. It may be fine for flicking through pictures, but what about more subtle gestures like pinching-to-zoom as the guy in the above picture is doing?

And something about waving my hand around in front of my phone or tablet just seems silly – almost as awkward as wearing a Bluetooth headset in public. Being able to flick through my phone's interface in the comfort of my home is one thing, but doing it where I may draw extra attention to myself is not something I want. The ability to switch seamlessly between the two is vital.

Gestures, however, are not the only thing taunting the touchscreen and its limitations. Engadget reported of a new technology made by researchers at Keio University in Tokyo, called RePro3D. This is a touchable 3D interface in which users can interact with projected glasses-free 3D images. The user can also feel feedback by wearing a tactile device on their hand or finger. I recommend watching the DigInfo video for the full effect, just try to overlook the guy in the video who talks about how "interesting characters" in animations and games make him feel "lonely."

Keep in mind that this demonstration from Keio University had absolutely nothing to do with cell phones or tablets, but such progress could eventually make it down the pipeline to our favorite portables. The cell phone market is plateauing andmanufacturers  will soon explore other options in terms of displays, input types, form factors and more.

Merging gesture and interactive 3D technologies into one could bring our Sci-Fi dreams Tony Stark's futuristic gadgets one step closer to reality. Even though I'm in love with the future and love to think about what crazy things we might see, I'm not so sure I'm a fan of gesture technology or holographic interfaces just yet. I'll opt to keep my touchscreen for now.

How do you guys and gals feel about gesture technology? Touchable 3D interfaces? Do you think they're the future of input for mobile devices? Or, like me, do you find flailing your hands and arms around in front of a device absurd?

Image via XTR3D, Discovery