So, you want to go beyond conventional, piano-style keys and guitar frets. Even if the ultimate goal is hardware, the touch interface of iOS is a lovely blank canvas on which to experiment. In the latest app, the work of UK-based graphic designer Paul Betowski, the Theremin proves a jumping-off point to other instruments, like the 1928 Ondes-Martenot, 1929 Trautonium, and the instrument used on The Beach Boys’ legendary “Good Vibrations”: the Tannerin or Electro-Theremin.

The new app is called the E Theremin – an Electro Theremin – but it owes more to the “Good Vibrations” instrument than the wave-your-hands-in-the-air original. So, while you may have seen Theremin-style instruments on iOS, this appears to be a first.

The sound is definitely retro, too, classic, simple analog in character.

(And, oh yeah, I still want more clever ribbons and strips in hardware.)

Reflecting on the design problem, Paul had a revelation. He explains to CDM:

My original plan was to make a iOS theremin, but I soon relised that it would be far more convenient to have the controls touchable; on screen, rather than using light intensity or gyro. But I definitely didn’t want to have a picture of a theremin with some images of hands that you move about the screen. So I remembered reading about [the Tannerin]. It had a slide control similar to the Ondes-Martenot.

I felt that having a slide as a pitch control would work well for iOS. So I ended up designing a synth in the style of the Ondes-Martenot and Electro–Theremin rather than trying to copy “no-hands” control of the Theremin.


  • 3-octave slide control.
  • Three oscillators, each configurable to four waveforms: (saw, square, triangle and
    sine), with octave shift, independent amplitude controls.
  • OSC2 set to unison.
  • Portamento, vibrato, and quarter-tones can be precisely controlled, says the developer.
  • Four presets, ready for performance.
  • Retina GUI support.

Nice stuff, indeed.

If you do want to experiment in hardware, there have been DIY attempts, like this brilliant-looking project covered on Synthtopia:
DIY Ondes Martenot MIDI Controller

It’s now discontinued, but I always loved the Persephone, for its sound and handcrafted design, from French builder eowave instruments.

And skip Wikipedia, you really want to head here to read about the Tannerin. Long live Paul Tanner’s legacy.

Hmmm - does this make anyone else want hardware? You can tell developer Paul is a graphic designer. Looks lovely - if you're going to do skeuomorphism, do it right. All images courtesy the developer.

Hmmm – does this make anyone else want hardware? You can tell developer Paul is a graphic designer. Looks lovely – if you’re going to do skeuomorphism, do it right. All images courtesy the developer.


  • http://twitter.com/peanutismint Peanut Turner

    This looks great! I have a similar Ondes Martenot app on iOS but what I really want is an app which will allow me to use my iOS device as a ribbon controller only, outputting pitch/volume changes over MIDI to my soft synths/Ondes Martenot samples…. Any ideas??

  • HappyILiveHI

    Looks lovely, but how different is this from than what can already be done by sliding when playing keyboard instruments in Garage Band?

  • http://agargara.iiichan.net/ agargara

    Cool app! I think the y-axis should be mappable to something as well, like in the touch theremin inside of SunVox.

  • Ben

    There is a persephone mkII : http://www.eowave.com/instruments.php?prod=63

  • James

    It doesn’t sound amazing, or all that theremin like. could really use some kind of vibrato features, because the ribbon isnt responsive enough to generate natural sounding vibrato.

  • Roger Pellegrini

    For those looking for an iOS ribbon controller to output MIDI, check out the “Time Space Keyboard” I wrote as part of Charlie Roberts’s free “Control” app:

  • Joe McGinty

    There’s also the Therevox. I just received mine and it’s quite nice: http://therevox.com/

  • Magic Cube

    Such a great application for music lovers! You may also like the new amazing Celluon Magic Cube, Bluetooth keyboard and mouse that provides an ergonomic way of typing on small
    devices such as iPads, iPhones, Tablets, smartphones and more. For more info, please
    visit http://magiccubestore.com/ a cool and ultra-portable,
    full-sized virtual computer keyboard.

  • MaxOrbit

    relised = realized