Dear REJ And jason would it be possible to add a folder just for caustic fin the files App on iOS?
While this would be nice, I can provide you a workaround while we wait to see what's coming:
Go ahead and download the GarageBand app. In the Instrument Selection menu, there should be an "external audio app" option.
Click that, and choose Caustic. Now, just load up your song, and get ready to play it. Go back into GarageBand and make sure you're recording, and then switch back to Caustic and hit play.
GarageBand is recording the audio from Caustic, so just let it play, and then you can export it from GarageBand after you've cleaned it up (trimming, adjustments, etc.).
This may have changed by now, but this is how I exported my music back when I had an iPhone 4S.
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