Over 25 years later, portions of MIDI introduced early on in the spec remain relevant. And if you want to connect your MIDI-equipped gear to Apple’s iPod touch, iPhone, and iPad mobiles, you will soon have an array of choices.

In iOS 4.2, best known for leveling the playing field between Apple’s handhelds and tablet, you’ll get full-blown MIDI support. It was clear in leaked details from earlier releases that Apple’s Core MIDI framework was finding new life on the mobile OS, but not directly what that would mean for hardware. Now, the hardware picture is clear. The Core MIDI framework appears to support two avenues for MIDI:

1. WiFi MIDI, via Apple’s own (apparently unique) wireless implementation, which should allow communication with other Apple handhelds and Macs, but likely not other devices. (WiFi is a common standard, but the way MIDI is transmitted over it is not necessarily so. That said, I believe the protocol for communication itself is based on documented implementation guidelines – not standards, but at least something someone else could conceivably implement.)

2. USB MIDI support for class-compliant devices, using the iPad Camera Connection Kit’s USB adapter.

More on the details – and other options and features outside just what Apple is giving you:

There’s one significant caveat to USB connections: the Camera Connection doesn’t carry a lot of current, so devices may require an external power source. So far, with multiple hardware adapters, and Apple’s own support for class-compliant audio, there could be a significant surge of hardware use with the iPad. But I haven’t yet seen indications these possibilities have taken the world by storm, even among Apple hardware devotees, perhaps because of the added bulk of the accessories themselves. (See more below.) That’s not to rule it out – I still think it’s pretty cool – but we’ll have to see how it’s received out there and how it works.

Interestingly, word of MIDI adapters has spread rapidly through the general tech press – outlets not normally excited by the vision of a 5-pin MIDI DIN connector. Developer Mike Keller, writing for PC World, has an especially ironic headline:

The Coolest New Feature in iOS 4.2 (That No One’s Talking About!)

So, why isn’t anyone talking about this? Apple’s NDA, which still covers 4.2, is one reason. (If anyone wants to have an existential talk with me about whether I should sign an Apple developer agreement and thus effectively gag myself as a writer, I’m game.) Another is that my sources tell me there aren’t yet code samples for the MIDI features. It could be fun to play with, though – especially with tools like libpd in development, bringing that popular free patching environment to the platform. And the good news is – this is public information – Core MIDI on iOS from the developer perspective should work just as it does on Mac OS. So huge kudos to Apple for high-quality implementation of a de facto standard for musicians.

The big news to me is that power requirements may prevent the use of some of the more compact devices out there — anyone want to test, for instance, the M-Audio Uno? Either way, it appears there may remain some call for specialized devices. Update: no worries! Reader reports suggest that at least the M-Audio Uno works fine, and that should mean other 1×1 devices are okay. (They don’t draw much power.) So, connect one of those suckers into the iPad, and you have a viable alternative to the MIDI Mobilizer. (Bonus: developers won’t have to set up an agreement with a separate hardware maker – for iPad, though you still need the MIDI Mobilizer on iPhone and iPod touch, since as readers note, they don’t support the Camera Connection Kit.)

So, aside from what’s coming in iOS 4.2, what are your options for getting MIDI in and out of Apple’s mobiles – or other mobiles, for that matter? Glad you asked.


2 MIDI in (5-pin DIN)
2 MIDI out (5-pin DIN)
Full 2.1A 5V USB power – enough to charge your iPad
Comes with an interface cable
2-4ms iOS app latency

The iConnectMIDI box is the most serious solution out there, especially with dualing ports. And lest you think it’s rendered irrelevant by the coming features in iOS 4.2, think again. Its dedicated connector cable and power specs should make it more useful with iPad than a stock class-compliant device. Buried in the specs document, too, is this gem: “iOS Core MIDI framework support, if and when allowed, is expected to further decrease latency for iOS applications.”

So it may get more useful, not less, with the 4.2 release.

Availability: Not yet. Stay tuned for NAMM.

Cost: Not known. I’m guessing $999/EUR1299. Kidding.

Development: Partner SDK, “as required” by Apple. That means there’s a test and verification process that you have to go through with iConnectMIDI and then you can submit to Apple and go through it again with them. I’m hoping that gets nixed with 4.2, but there’s absolutely no word soon (not even if you break NDA).

Line 6 MIDI Mobilizer

1x in MIDI DIN, 1x out MIDI DIN (via 5-foot breakout cables – they use a 2.5mm connector on their actual box)
Specialized hardware adapter
Includes a free app for recording, exchanging via email and WiFi
iPhone, iPod touch, iPad (a nice handheld option on the former two)
Already supported by a handful of apps, including Line 6’s own MIDI Surface
Developer program open to anyone; see above

Availability: Now
Cost: US$70 street

The MIDI Mobilizer has the advantage of being relatively portable, though as some readers have pointed out, it still adds some bulk to Apple’s svelte handhelds. It’s also costly given what computer users are accustomed to paying for similar interfaces. But once you’ve got it, it’s a powerful, handheld tool. The big question mark has been app support, so watch, again, to see if what we get via 4.2 is standard support in place of individually reviewing apps.

See also SonicState’s review:

WiFi MIDI, OSC, etc.

Readers gripe that the big problem with MIDI adapters is that they kill the portability of the device, thus, erm, defeating the purpose. After all, for $200 these days you can get a netbook and add a $30 MIDI adapter with a lot less fuss, if you want a more portable MIDI rig.

That makes wireless Internet look more appealing, not only on iOS, but potentially other mobiles, too – like Android or even game gadgets.

One example:

DSMI, the DS Music Interface, is free software that has been ported to iOS and enables wireless MIDI communication not just with the Mac, but Windows and Linux, too. (I’ll be interested to see if new implementations of the WiFi MIDI used in 4.2 for those platforms can do the same.)

And that’s to say nothing of various wireless OSC implementations, enabling cool apps like the one we saw earlier this week. If you don’t mind a computer as a go-between, that’s another solution for MIDI right now:

Bluetooth? (on Android?)

What about Bluetooth? Recent conversations I’ve had with engineers on the phone suggest that latency and jitter should no longer be a problem with modern chipsets. That could make Bluetooth an ideal way to enable both mobile platforms and hardware wirelessly.

Just one problem — iOS’ restrictions on device pairing appear to rule out the use of this technique on Apple platforms.

Android is another question; I’ve already seen a couple of proof of concept tests that suggest that this would work really well on Android.

Here’s hoping eventually Apple allows something similar, even via Core MIDI. In the meantime, it could be worth trying on Android. That’d open the possibility of cross-platform mobile-friendly apps that used WiFi and cables on iOS and WiFi and Bluetooth on Android.

Who Cares?

So, why bother keeping track of this? I think there are a few scenarios that get interesting with these devices:

  • Mobile music: Get away from your desktop computer and its distractions and work in any environment. (Hey, even the original Nintendo Game Boy can be adapted to MIDI I/O.)
  • Alternative sequencers: Since touch control has often been relatively lacking on desktops – and laptop form factors in particular don’t lend themselves to touch in their standard hinged form factor – touch-based software on a system like the iPad (and soon, other tablets) benefits from these approaches.
  • Mobile interfacing with gear: Imagine you’re in a studio full of vintage synths and want to record something, without finding a place to balance your laptop.

There’s also just the simple fact that an iPhone, an Android phone or tablet, and an iPad are all computers. Part of what we’re seeing really is reinventing the wheel – in a good way. We’re getting the standards for interoperability and actual music making we’d expect on any computing device.

Stay tuned for when the 4.2 NDA is lifted (and we have the 4.2.1 NDA to contend with instead). And for discussing non-NDA platforms, or iOS once its NDA is lifted, I hope you’ll join us in these groups on Noisepages:
Next-gen Mobile Music + Visual Dev Hack Group
Pd Everywhere

Meanwhile, if you want to see MIDI on traditional computers, a couple of us have found that the good old-fashioned MIDI multi-port hub has some utility, for reasons I’ll explain soon. And yes, you can still buy them – check out the M-Audio MIDISPORT 4×4. So, no, I’m not only about the mobile stuff.

  • Armando

    peeing my pants

  • Totally stoked about this.

  • steve jobbbs

    are you that lazy to push the keys and turn the knobs on the actual keyboard.

    someone needs to make a app for the ipad to wipe their ass with.

  • its gonna be amazing, in my opinion, the biggest step forward in mobile music!

    P.S. there is a predicted price for iconnectmidi: $199.99 here a link to the faq pages on their site that says this:

  • hookeypookey

    Oh come on, like Android is ever going to have something like CoreMIDI.

  • Mahko

    @steve jobbbs: i'm pretty sure that video is what is known as a "proof-of-concept." use your imagination a little. StepPolyArp hooked up to a synth would be pretty badass, for one thing.

    @swalker133: no way i'd pay $199 for it. maybe $100, max.

  • Peter Kirn

    @hookeypookey: Right, because MIDI is so damned hard.

    Uh… no.

    MIDI is quite easy to implement. Developers are just really waiting on consistent hardware support, which is another matter. Having something like Core MIDI is nice, but not absolutely essential — have a look at DSMI, that Nintendo DS and iOS MIDI implementation.

  • Don't forget The Missing Link.

  • panic

    I continue to fantasize that someday I will be able to control my beloved, beleagured little red & silver synth in real-time without a mouse.

    iConnect MIDI & Line6 MIDI Mobilizer seem like 2 possible ways to do so.

    Truth or fantasy?

  • panic


    that would be my Micron.

  • woofkinhoo! still won't stop touch osc being the best thing there is on the iphone/ipad tho…

  • Peter Kirn

    @matrix: good point … I guess that's just a prototype, though? In a way, that really fits under the OSC category.

    @panic: truth. You can pick up a MIDI Mobilizer and do it right now.

  • Billy Gaates

    Steve Jobbs – you are an @$$ – this is going to be very cool and if someone comes up with an app to wipe me that will be great. If they can do it via MIDI – even better.

  • Charlie Lesoine

    Steppolyarp now works with the line6 midi mobilizer! Stoked!

  • Trying to raise a child and stay sane, I've wished I could wire my little Akai LPK25 keys to my iPhone and just have a USB cable and a headphone wire coming out of my pants pocket, with the keyboard resting on top of the stroller as I walk around the lake. Akai is now selling a larger iPhone dock keyboard, so they have no incentive to help, and one more tabletop item doesn't solve my problem. Most of this is about iThings as midi triggers. What about adding physical keys to my iPhone synths? Are there essential things I'm missing, which already exist? Does anyone know if the Akai software for iPhone can support inputs other than the Synthstation? Apologies if this has been explored before.

  • @hookeypokey: well, the android version isn't quite done yet, but ..


    (hint: ipMIDI is a documented standard for transmitting MIDI via an IP network, and there are implementations for all major OS's)

    oh, you'd settle for maemo (nokia) ? ok then:


    all praise to rui nuno capela, author of so much wonderful stuff that i've run out of space to mention anything else except QTractor …

  • trash80

    The uno powers up just fine- no "not enough power" or unsupperted message.

  • Peter Kirn

    @trash80 – great news!

    @Paul: ipMIDI seems like the better way to go for compatibility between platforms, no? From what I could see, Apple is doing something unique to them.

  • heisenberg

    Must resist temptation. Wait, wait till second rev of iPad.

  • "The iConnectMIDI box is the most serious solution out there"

    Thanks, we like to think so – we intended to design a device that is suited for the professional and keep to a high end consumer price.

    We have been experimenting with CoreMIDI support – we cannot say much right now – stay tuned…. I will say though, our previous FAQ of 2 to 4 ms latency to iOS – way overstated now with CoreMIDI.

    More information when we can post it….
    http://www.iConnectMIDI.com http://www.twitter.com/iConnectMIDI

  • Leslie

    M-Audio UNO interface does NOT work and for obvious reason – it uses propriety drivers which means is not plug & play and therefore not supported by iPad.
    On the other hand Behringer BCF 2000 is recognized correctly and so is my Novation SL 37 when used with batteries, but sadly none of the Apps I have on my iPad recognize CoreMIDI devices yet…

  • Bynar

    I'm waiting for the "iPad Pro" that will run Logic. No, maybe it might just be better to have a pad like interface to use in conjunction with a traditional laptop and or desktop computer. I hate the mouse interface but I'm not so ready to give up my keyboard (considering that I now live in Renoise).

  • Very excited to see this! As much as I love the conveniences of wireless technology, it's just not reliable. OSC data over a private wireless network works great until 10,000 people enter your venue and turn on their wireless devices. Until that's stable, wired is the way to go for mission-critical control.

  • Robman84

    Peter, Unless Apple does the decent thing and allows the camera kit to work with iPhones and iPods then I think the line 6 midi mobilizer still has a use.

    I am very excited by 4.2 and can't wait to try it. Here's a thought for buss powered devices – could you use one of those USB dual power cables that you get with some external disk drives and attach the other end to something like the duracell instant power thing that provides something like 35 hours of 5v power? I might give it a go with my nanopad tonight.

  • Rowan Pope

    The awesome Nanostudio app works brilliantly with the Line6 MidiMobilizer. Akai SynthStation support is in the next update. But CoreMidi bodes well for the future. I agree about Apple needing to allow the camera connection kit on the iPhone.

  • jonah

    Something I've been wondering for awhile is how come there aren't wireless midi dongles? Is it a technical thing? Little midi plugs that you stick in the back of your keyboard(or whatever) would be so useful.

  • This is AWESOME! Wrote a small post on this and posted and soundsector, linking back to this article so hope you don't mind D:

  • Leslie

    Here is another one tha does NOT work – Roland/Edirol PCR-1.
    Again, this is due to propriety drivers required and not being plug and play.

  • Pete Goodliffe

    Code samples for basic CoreMIDI support are available here… http://goodliffe.blogspot.com/2010/10/using-corem

  • Pat

    @ Jonah. M-Audio does make wireless midi dongles.


    I'm really excited about the possibility of replacing my MacBook with an iPad for live performance. I play in a band and I trigger audio and video samples using ArKaos. The software is great, but if I could install it on an iPad, that'd be awesome! The trick would to somehow get VGA video out and midi in both through the dock connector at the same time. Maybe the next version of iPad will have a dedicated display/monitor output?

  • Peter Kirn

    Well, there is a standard connector out there that does allow all this simultaneous I/O, but I doubt Apple will adopt it – they're too invested in the Dock Connector. Maybe if they did a breakout, depending on whether there are enough pins for the connection. Various Android devices have all this I/O on paper, but there's no platform support — not yet.

  • Mark

    First of all, great collection of info on the topic.

    Here's to hoping that Android catches up sooner than later.

    There seems to be a lot of interest from people to contribute to the development of a midi api for the platform. Google needs to learn that it's the niche 'gee wiz' apps that sell a device, even if people don't know how to really use the app they love having a device that can do cool things – and MIDI can do a lot in that way.

    FingerPlay is a cool proof of concept on Android but doesn't work with hardware synths as you can't map midi CCs. Great for software synths though. There are a few others but you can really tell there's no serious music back end. …enough rambling.

  • bensur

    @Mark that's because google doesn't give a shit about music or music production. Rather, the android team. There are plenty of music producers at Google, I know for a fact, but their business model has no room for such concerns.

  • bensur

    On the contrary, Apple has at least 3 separate departments concerned with people who want to make music. That's just the way it is.

  • Peter Kirn

    @Mark: What functionality would you want from Android for MIDI? (I'm not sure an OS-level API is actually what you want.)

    Would you absolutely have to have hard-wire MIDI support, or would wireless communication be sufficient – and under what circumstances? (That's really a fundamental question for all these platforms.)

    @bensur: Uh, okay. Google has some 20,000+ employees worldwide. The subtleties of music concerns are going to be in the minority at any large tech company.

    Apple has an extraordinary wealth of expertise and care when it comes to much. But I've had conversations with everyone from mobile handset makers to developers, and been frankly surprised at the degree to which people *are* interested in what happens with music creatively. I'm inclined to give those folks a chance rather than make sweeping judgments.

  • Our latest video, showing use of the built-in OSX MIDI Network driver to wirelessly control Logic from Pianist Pro. Coming also in V1.8.


  • The protocol Apple uses for MIDI-communication over the network on OS X and iOS 4.2 is based on the RTP-MIDI-specification mentioned before.

    My Windows-driver (www.tobias-erichsen.de/rtpMIDI.html) is compatible to both OS X and iOS – so apps written to use the Core MIDI api on iOS will also be able to connect to Windows based PCs with my driver.


  • We wanted to let everyone on this thread know about another solution for Wireless MIDI control. The Missing Link (http://www.wifimidi.com/) enables any iPad/iPhone/iPodTouch to become a MIDI remote via TouchOSC. One of the huge advantages of this solution is the complete elimination of the reliance of any sort of computer in the chain. Please feel free to contact us with any questions. Thanks.

  • Fil

    For me M-Audio UNO is working, connecting my Yamaha digital piano by standard MIDI cables, obviously using Apple camera USB connection…
    It's acknowledged in GarageBand allowing to record stuff on a true touchsensitive keyboard…… 😉