How do you record audio directly from iOS

Question

My app involves creating and recording sounds you make within the app. I have tried multiple ways of recording like AVAudioRecord. So far these only offer a way to record through the microphone but I want to record the actual sounds made within the app. How on earth do I achieve this. I've been on this for days, can someone please help me, thanks!

I also use Audio unit for playback in my application.

This is what I have so far using AVAudioRecord:

_audioController = [[AEAudioController alloc] initWithAudioDescription:[AEAudioController nonInterleavedFloatStereoAudioDescription] inputEnabled:YES];

- (void)beginRecording {
    // Init recorder
    self.recorder = [[AERecorder alloc] initWithAudioController:_audioController];
    NSString *documentsFolder = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES)
                                 objectAtIndex:0];
    NSString *filePath = [documentsFolder stringByAppendingPathComponent:@"Myaudio.aiff"];

    NSLog(@"%@", filePath);
    // Start the recording process
    NSError *error = NULL;

    if ( ![_recorder beginRecordingToFileAtPath:filePath
                                       fileType:kAudioFileAIFFType
                                          error:&error] ) {
        // Report error
        return;
    }
    // Receive both audio input and audio output. Note that if you're using
    // AEPlaythroughChannel, mentioned above, you may not need to receive the input again.
    [_audioController addInputReceiver:_recorder];
    [_audioController addOutputReceiver:_recorder];

}