Audiobus: Use your music apps together.
What is Audiobus? — Audiobus is an award-winning music app for iPhone and iPad which lets you use your other music apps together. Chain effects on your favourite synth, run the output of apps or Audio Units into an app like GarageBand or Loopy, or select a different audio interface output for each app. Route MIDI between apps — drive a synth from a MIDI sequencer, or add an arpeggiator to your MIDI keyboard — or sync with your external MIDI gear. And control your entire setup from a MIDI controller.
Download on the App StoreAudiobus is the app that makes the rest of your setup better.
MODSTEP questions / features
Modstep rocks! Haven't been using it much but I will from now on. A few questions:
SCALES are great, I was hoping that the key/scale changes would apply to specific segments or to specific clips but they seem to affect the whole track 
Is there a way to apply a key or scale change on a specific clip segment independently of others? That would be awesome for writing and modulating pre-written parts.
Edit: thanks to some helpful replies, you can change the scale and the root note per scene by tap holding a scene. For those who didn't know already. Not exactly what I was after but close.
SWING, similarly can we tweak the swing of a specific clip (or at least a specific track) rather than the global swing setup?
Any UNDO / REDO?
MODULATION. This part is still confusing to me and I need to give it more time. Is it possible to record / draw / edit the midi modulation of any synth parameters? For example can we tweak Moog Model 15 and have Modstep record the modulations and can we then edit the modulations recorded or draw new envelopes?
Thank you!! And if the developers are reading, big up and much love.
Comments
My impression was that scale adjustment was used for inputting notes and filtering the visual display only. I seem to recall when I switched scales I still heard the notes I input from the previous scale I used. It has been a little while though, or maybe this changed.
UNDO, yes. Baffling that it's not there. Hoping it is in the next update. The workaround is to rename the file upon opening, and if you need to undo, go into the autosave and find the oldest file you can. It makes me fantastically anxious to do this.
MODULATION? Anyone?
My question: I have a nice little melody that is dispersed over three different clips. Any way to copy the midi from one clip into another clip? I have the idea to perform the melody by playing the clips in time and recording the midi out, then reimporting into its own clip. But that seems complicated.
@AudioGus changing the scale/key does change the notes you year, that's the beauty of it. It transposes everything in the selected scale/key.
For writing purposes I'm just trying to apply those changes to individual parts or clips rather than the whole track.
Oh I see, in the clip you can set the scale. I always just did it on the keyboard which is 'non destructive' as I described.
@AudioGus it's a powerful feature for switching the "mood" of smth you wrote. I wish I could apply it per clip. Seems strange that you can only apply to the whole track. Messy but I can probably duplicate the track to achieve that.
It looks like duplicating tracks doesn't seem to do it.
A potential workaround (granted not ideal) could be to work in 'None' and when you manipulate scale, export the clip as midi and re-import it back into 'None'. That way you still get the scale transposing as a tool.
Acck, no midi import on a clip I can see.... hmmmm, must be a way...
Oh just turn off 'Global Scale' then at least you can set it per track.
BTW: thanks for showing me this!
Yes, I'm not home but I'll try this. Turning off global scale might do it. Such a shame it's not per clip, I wonder why.
Yah it does do it... totally works. Kind of nice to group scale by track though then you don't need to clip dive.
Oh snaperoo homee, you can do it per clip... Sorta.. Check out the scales on the right...
@AudioGus niiiiice! So we can do it per scene. It's always better than per track. I was looking on the wrong place, in the piano roll.
Ill try this tonight. Thanks
Cool man, yah its time I got to know Modstep again. Haven't caught up since the last big update but am currently (f)unemployed so time to play.
Does Modstep support BT MIDI ?
Currently no. There is a free (donationware) app called Midimittr that should do the trick.
MidiFlow also supports BT Midi and for simple use , "Apollo Midi over Bluetooth" is great and can run on iOS 7. (no ipad2 or iphone4).
I hope they implement expressive midi MPE (Multidimensional Polyphonic Expression) to record MPE synths like Animoog, Model 15, and MPE keyboards like Seaboard, Linnstrument...
And swing per clip.
And audio recording
Thanks
@Korakios thanks for the tips, I had no idea this was possible
@AudioGus yes Modstep seems to have a learning curve, it's deep and layout is somewhat unusual, I found it (like many) disturbing at first.
The audio clip recording function is great, sort of a bounce. Wish it wasn't organized by folder. I Imagine you can slowly build libraries of your own samples and patterns to use and edit in other projects or in another DAW. This is going to be useful.
Spent the last few hours with it. Damn, is it good.