How to record user generated sound output on iPhone
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So I have a series of sounds that a user will play and rearrange and edit etc. while using my app.  When the user is finished, I want them to be able to save their work and record it to an mp3.  I don't want to just play it through the speakers and record with the mic as that will result in low sound quality and interference.  I cannot think of any ways of doing this that doesn't require extra hardware and/or a computer.  How can I do this using just their device?