XTouch turns any surface into touch-enabled controls for iOS apps

XTouch Commercial/Proof of Concept – make every surface tap sensitive from Vladimir Druts on Vimeo.

XTouch, an SDK created by a group at the University of Toronto’s Mobile Applications Lab and funded by JOLT, turns any surface into a touch-sensitive controller for iOS apps with no additional hardware. Since XTouch uses acoustics and vibrations to recognize taps on a surrounding surface, the only requirement is that your iPhone or iPad is placed on the same surface you want to use as a touchpad. An SDK is coming soon that will allow developers to think up many interesting implementations, but for now the company has released two apps that show off what XTouch is capable of.

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One of the apps, Voodoo Tap Frogs, was recently recognized by Apple as a best new iPhone/iPad game in the App Store, but has yet to get any mainstream attention. It has up to four players sit around a table (or any flat surface), each tapping the table in front of them to control an onscreen character. It’s featured in the video above and is debuting alongside another other app just released by XTouch, Magic Xylophone.

Co-founder Parham Aarabi explained to us how the tech works:

“The XTouch technology works with any existing device that has at least one microphone.  No additional hardware or sensors are needed.  It ‘understands’ the unique acoustic signatures generated when you tap at different locations on a table, and after a quick calibration phase, where ever you tap, the sound is classified and based on that we come up with a location estimate.

Essentially, we have way to distinguish the subtle difference between different tap sounds on a surface in order to find out where someone is tapping/touching.”

By using a surrounding surface instead of blocking the display with your hands, the platform opens up a lot of opportunities for apps and games to implement collaboration features by allowing input from more than one user. It could also come in handy for a lot of applications where tapping a surrounding surface may be more convenient, such as tapping your nightstand to silence your phone’s alarm clock or a countertop to interact with a cooking app or answer a call when your hands are dirty.

The SDK is arriving sometime in Q2 for developers, but you can check out the technology in the two apps released by XTouch.

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  1. fanaticalabouttech - 9 years ago

    Seems like a cool idea, interested to see what this could have in store in the future.

  2. Mr. Grey (@mister_grey) - 9 years ago

    What a horrible video (in terms of describing the product) for an idea of dubious utility.

  3. Arch Angel - 9 years ago

    April Fool

    • irelandjnr - 9 years ago

      Sounds like an April fool alright, but it’s not. Just tried the touch xylophone app out and it definitely works. The only problem I see is for me it wasn’t accurate enough. Perhaps I need a harder surface to better distinct sound locations for sending the tap audio to the mic. I need to tap to hand and my night stand was not a great surface for it. You definitely need some kind of stickers on the surface to remember where you tapped, though. Their marketing video is embarrassing the way it shows glowing rings of light that obviously don’t happen outside of their advertisement.

  4. Markus Meixner - 9 years ago

    PLEASE could you test such apps before promoting it on 9to5mac? I just spent 10 minutes of my life in vain. It’s absolutely not working. This app is not able to distinguish my knocks on different spots on the table. And if it would – I would have to position the phone exactly at the same position every time I use this app….

    • Jordan Kahn - 9 years ago

      I did test the apps. They worked great for me, but better on some surfaces than others.

    • Parham Aarabi - 9 years ago

      Markus, try starting with just 2 tap locations. That should be working very accurately (if it is not, for some reason, please let us know). Your comment regarding the position of the phone, that is unfortunately true. Every time you move your device, the acoustic surface signatures completely change and so you have to recalibrate.

  5. PMZanetti - 9 years ago

    That is AWESOME. Opens up a whole new level of what these devices can do. The tapping of the nightstand to silence an alarm, and tapping the kitchen counter while cooking…..and kids banging the table instead of the iPad……brilliant examples. I want all 3.

    • PMZanetti - 9 years ago

      Edit: Just tried X-Touch and if that is any indication of its level of accuracy….its worthless.

      • Parham Aarabi - 9 years ago

        Peter, I suggest starting with just two tap locations on a solid surface. There is a bit of a learning curve but once you get the hang of it, it’s actually fun to use (and works fairly accurately).

    • Ryan Roskey (@Rroskey) - 9 years ago

      yeah it is crap. the iPad would need several new mic for this to work. I tapped on the other side of the dice and it was still logging another pout on the opposite end

      • Parham Aarabi - 9 years ago

        Ryan, actually localization with a single microphone is possible. Multi-mic localization is of course possible too, but that also has its own issues. It is surprising how much info you can extract from just a single microphone. Is the single microphone case always accurate? No. But if you try the app on a hard surface, you will see the merits (and challenges) of the XTouch approach. I would suggest starting with just 2 locations on opposite sides of the device to get a feel for the interface.

  6. Shia LaBouef seems to be doing a much better job in choosing his movie roles these days.

  7. amitvedant - 9 years ago

    Good concept, will be great if developed properly. Good luck!

  8. Jesse Supaman Nichols - 9 years ago

    Props to the developer for thinking outside of the box! It is always cool when one can discover a new way to use existing technology! It reminds me of the guy who used the phone vibrations to do the Panoramic photos!

    Unfortunately, the implementation is pretty bad right now. It seems to be very inaccurate. However, with some improvements to the algorithms… This could have a lot of potential!

  9. Nikolai Mikkelsen - 9 years ago

    I see use of this in some machine control applications. When this app is fully functional would very interested in testing it further.

  10. Patent claim: TableDrum (released in 2011 I think)


Avatar for Jordan Kahn Jordan Kahn

Jordan writes about all things Apple as Senior Editor of 9to5Mac, & contributes to 9to5Google, 9to5Toys, & Electrek.co. He also co-authors 9to5Mac’s Logic Pros series.