title: AVAudio detect note/pitch/etc. iPhone xcode objective-c
body: <p>I'm making an app on the iphone and I need a way of detecting the tune of the sounds coming in through the microphone. (I.e. A#, G, C♭, etc.)
  I assumed I'd use AVAudio but I really don't know and I can't find anything in the documentation.. </p>
  
  <p>Any help?</p>