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:

Critics frequently attach the phrase “lock-in” to Apple’s iTunes Store – iTunes – iPod/iPhone combination. But, in the post-DRM age, what does that mean, exactly?

First, you have to recall that while for many of us the manual drag-and-drop music management is appealing, it isn’t so for many average consumers. They want sync. That means that music will be stored in iTunes and synced to Apple devices and nothing else. Apple is serious about locking you to their store and their devices, enough so that they frequently update their software with special keys that prevent the use of devices. iTunes is “free,” but Apple determines which mobile devices you can use and which you can’t. And Apple has gone after anyone who dares give you the ability to use your own music software or own devices, including efforts (ironically) to make their iPhone and iPod work with Linux and open source players.

These efforts don’t protect the music or prevent privacy – they protect users of Apple’s software and mobile devices from using anything but Apple’s tools. Yet Apple has used the Digital Millenium Copyright Act to take legal action over anyone who dares to even talk about how to use legally-purchased music and hardware:

OdioWorks v Apple

Perhaps suspecting their case was too thin to defend, Apple eventually backed off that particular claim — after, says the Electronic Frontier Foundation, “7 months of censorship and a lawsuit.”

Apple Withdraws Threats Against Wiki Site

But the software and hardware locks are unchanged. And Apple has won, in my view, an even more important battle: they have a monopoly over mindshare.

Mint.com, the online financial management tool, has put its numbers together with market researchers NPD Group to analyze music spending. The results: when it comes to consuming recorded music, digital music continues to rise. At the same time, so does Apple’s grip on the music consumption market, a combination that includes proprietary control of a music store, a music player, and the leading mobile device.

Digital technology has transformed the listening experience. But there’s little in the way of physical artifacts of that act, and a diminished sense of humanized relationships to an individual being at the other end. From modern radio to Internet-streamed playlists, our listening world is DJed by automated robots in streams that flow through generic, mass-market speakers. The object and the content lack the design intention that imbued, for instance, the gorgeous radio sets of the early 20th Century and the personalities that narrated the programming.

Armed with a lasercutter, designer Matt Brown has a novel concept for how to redesign the act of listening. From the creator’s blog Real Tomato:

Rounding up my catch-up-on-iPod/iPhone-stories, here’s one from the developer perspective – one that could face music creation developers on the entire platform.

The Apple iTunes App Store now faces the risk of becoming a victim of its own success. Music applications could be a big part of that, without some adjustments on Apple’s part. The problem is this: incoming music “fan” apps could flood out the music production apps that had enriched the mobile software platform since its debut. I think the need could be really urgent. Consider that part of the appeal of Apple’s mobile platform – yes, even in stark contrast to the Google Android on which I’ve been developing myself – is its spectacular real-time audio tools. Combine that with a disproportionately large number of Mac-using musicians, lots of ingenious apps build on Apple’s Core Audio platform, and we’ve seen a mobile platform with an extraordinary number of tools for music creation.

The problem now is that that unique set of powerful apps could get overwhelmed by essentially unrelated “music” apps. A developer who has asked to remain anonymous is already campaigning for a change. He does a good job of explaining the issue, and what might need to happen to fix it. If you’re a developer, you can add your support and feedback to the idea.

Here’s the full explanation: