Does anybody have experience with AUs on iOS?
I understand we can now compile our plugins as AU’s for iOS and sell them on App Store, but what is it really?
Do we need to bundle/deploy it with a App somehow or will it automagically also run as a standalone app?
Is there any good Apple links with more information? (google didn’t give much insight)
Here’s how it works with JUCE 4.2. Also check out examples/AUv3Synth, it’s an example app we put together that illustrates all this.
Now you can compile your audio plug-in for iOS. It will create a Standalone app target and an AppExtension target:
If you compile and run that Standalone app on your iOS device, it will run your plug-in with a minimal standalone wrapper around it (essentially a full-screen app window and audio/MIDI input+output hooked up automatically). You can also customise this standalone no-host view so it looks different from the usual plug-in view if you like (adding a keyboard component and what not).
But the main feature is that once you run that app on your iPhone/iPad, it will automagically register the AppExtension version of itself. From that point on, this AppExtension (the actual plug-in) will be loadable on AUv3 iOS hosts like GarageBand and Cubasis.
If you have a JUCE licence, you can then go ahead and sell your app on the App Store!
Ideally this iOS port should even work out-of-the-box with your existing plug-ins. It’s pretty cool actually. Have fun!
Does JUCE automatically recognizes the iOS Touch Controls?
Don’t know… what’s that?
If you mean gestures, then no. That’s a feature we’d love to add but didn’t have the time to do that yet.
Yeah the gestures. That would’ve been cool
Yeah. Some day. Hopefully soon 
You can also customise this standalone no-host view so it looks different from the usual plug-in view if you like (adding a keyboard component and what not).
I wanted to ask how to customize it, but found it. Here’s how:
JUCE_USE_CUSTOM_AU3_STANDALONE_APP=1 to the Extra Preprocessor Definitions in IntrojucerSTART_JUCE_APPLICATION(YourApplication) somewhere in your code, where YourApplication is your custom subclass of JUCEApplication.