You’re now approved to DJ with your iPhone. Or at least the app is. I’m not sure if I can take credit for getting Apple’s attention, but Apple has approved the TouchDJ application from Amidio. That’s big news, partly because developer Amidio has consistently been at the forefront of musical development on the platform, including their Noise.io synth and wild hexagonal JR Hexatone Pro.

This also is a big blog to the theory that Apple is intentionally blocking DJ apps — and a big boon to the theory that the App Store is just plain clogged, even if it may be disproportionately affecting more sophisticated applications.

Features in the release:

• “Visual mixing,” with a clever interface that uses overlays atop side-by-side waveform views
• Pre-listening using a special left/right adapter
• Faux vinyl and spin effects
• Real-time scratching, looping, positioning, EQ, effects, re-pitching
• Onboard sampler with 3 WAV sample slots, recording from the mic
• Uses a separate MP3 library with companion apps, since it isn’t possible to DJ from the library you sync from iTunes

Now, to me, that last point is a fairly significant one. You have to load tracks you wish to DJ separately, in MP3/M4A format. And I’m sure that this will start various debates about whether you’d want to DJ on your iPhone in the first place. But don’t look at me — I just work here. I’d be remiss if I started out the week talking about apps stuck in iPhone limbo, only to ignore them immediately becoming available. And I will say, Amidio is one of the smartest mobile music developers out there, so it’s worth checking out the range of what they’re doing.

Whether petitions and news stories did help this app to get to the top of the queue or not, I have no idea. I think maybe I’ll start running screaming headlines with things I want in them, if only for good luck.

Tomorrow on CDM: “You Know What Annoys Me? The Fact That We Don’t Have Unicorns. Magic Unicorns. Who Speak OSC.”

A powerful DJ application for your iPhone or iPod touch may be a tantalizing prospect. But several would-be candidates aren’t available to you yet. Why? They’re languishing in Apple’s approval process, with no sign of whether they’ll be released or not.

For all the success of Apple’s App Store, some developers and users continue to express frustration at what they believe is a sluggish, unpredictable approval process, restrictive Apple policies, and Apple’s complete control over distribution and categorization. That now leads to two complaints from music developers. A number of music developers want more delineation from Apple’s categories, so that the flood of general music apps don’t drown out powerful, creative tools. Meanwhile, developers of DJ applications claim that Apple is discriminating against DJ apps, which they say has led to delays without explanation.

“Open” development is relative, without question. Game system makers require developers to prove to them why they should be “allowed” to create titles, leading to a tightly-controlled stream of approved titles. But the success of Apple’s relatively open development model has prompted many software creators to hunger for greater freedom. I’ve increasingly heard people enthusiastic about the more flexible distribution model on Google’s Android (and other Linux) platforms, which allow users to install apps they want. I even moderated a mobile music platform panel at the CMJ music conference at which a Verizon representative, no less, talked about wanting to be more open to applications. The benchmark was Apple, for being perceived as overly restrictive.

iPhone/iPod touch developers, however, aren’t simply ranting against Apple. They’re complaining because they’re enthusiastic about the App Store. They want changes from Apple and believe there’s potential to get what they want. That said, I think they also illustrate potential for rivals like Google to outdo Apple – assuming those rivals invest more time and effort into courting these kind of applications.

Is Apple Blocking DJ Apps?

First, some developers believe that Apple is intentionally blocking DJ applications from being approved. Whether intentional or not, a number of potentially ground-breaking applications are unavailable after a significant delay. Kasabian Kasabianmeister writes:

As computer music practice – part composition, part instrumental play – spreads, the idea of software interface as performance tool is becoming second nature. Putting those opposable thumbs and sensitive fingertips to work, multitouch controllers are growing in number, variety, and sophistication. Berlin-based artist Marco Kuhn shows off his beautiful creation, the PlayBox multitouch hardware, and its first app, PlayLive. That first software focuses on Ableton Live performance, but Live could be just the beginning – Marco has worked with Pd in the past and promises other apps to come. He’s interested in selling this device in the future, and he shares with us the tools he used to create this work for those of you doing development along similar lines.

Imagine drawing an interface on paper, then being able to use it as a musical interface. Or, heck, don’t imagine it – do it. Unfortunately, the kinds of intelligence necessary to make the music video in yesterday’s post just aren’t practical yet. (That is, you could draw a picture of a keyboard, and even use the picture as a music controller, but while you or I could recognize a keyboard from a drum pad and know that line is a fader, a computer would need some sort of advance structure for any recognition to work.) But you can do some really clever things, as folks have shared in comments.

And using some basic paper interfaces, you can make entire instruments for just a few dollars.

Of course, the awesomest way to do anything is with LAZORS. Greg Kellum and Alain Crevoisier presented a paper at last year’s NIME (a conference for new interface designs for music) proposing a system for making any surface a control surface. Like the music video yesterday, you can configure your surface to function however you like – even dividing it up into pads and faders.

By now, you’e likely seen plenty of multi-touch interfaces or means of tracking hands. But, to paraphrase the NIME paper, these either require a special surface (or transparent surface), or they can’t actually detect when you’re touching. You can even use multiple cameras or an IR beam, but there are limitations to accuracy and the size of the usable surface that would result. Kellum and Crevoisier use an infrared camera and two illuminators, each built by pointing a laser at a mirrors.

Yawn, you say, been there, done that, seen Jeff Han’s video… The advantage of this system is that you can use any surface, like your dining room table. And you can configure that surface however you like. There’s even a freely-downloadable Surface Editor you can extend in Java and Processing. The creators claim they can even get input latency down to a reasonable 10 ms using high-speed cameras.

Transforming Ordinary Surfaces into Multi-touch Controllers [PDF paper, NIME 2008]
Future Instruments > Projects
Thanks, Randy Jones!

db3ll has created a keyboard out of paper, and of course it works better than those flimsy rubber “roll-up” pianos you see for sale. “Conductive ink is what I used,” he says, “painted on as traces on the non-printed side of the paper.” That’s the twist – I had assumed you’d use the top of the paper, but the trick is to use the reverse side to provide the “wiring.” He also offers advice for making a fader:

It’s still anyone’s guess exactly what fruit parent technology maker Stantum may soon ship, but the JazzMutant Lemur touchscreen is getting a component update soon. Nat Lecaude points to a quiet MySpace post from JazzMutant with the details of a coming manufacturing change.

“…the next batch of Lemur will feature the latest generation of our multi-touch technology: better optical performances, higher precision, greater accuracy and responsiveness. It will be clearer and have brighter colors. We plan on launching the new Lemur in early October, and of course we will keep you updated as we get closer to launch date. We once again thank you for your patience, and look forward to sharing the excitement early October!”

It’s actually quite remarkable to me that JazzMutant remains alone in this market – and with Stantum focused on the mass market, that could be the case in the future, too. The issue is that doing multi-touch well still costs some money. There are basic implementations on computers that are cheaper, but that restricts you to a few computer models, because slapping multitouch overlays on displays remains pricey. So HP can get a few computers to the mass market, but not without cutting some corners and not even on that company’s full range. The iPhone has brilliant multi-touch control, but a mobile form factor makes this much easier.

I’ve got some videos demonstrating what’s possible with the Lemur coming soon, as well as some notes on how the software has evolved since I first saw it in its initial release. Even if you don’t want or can’t afford a Lemur, it’s a fascinating demonstration of interaction design and OSC, with lessons (inspiring and tough alike) for other interfaces.

Photo by Rainer Knobloch for CDM.