How can I redirect the mic input to the speaker output on an iOS device? I know it feedbacks overtime, but how can I do it in code?
See aurioTouch sample from Apple. That does exactly what you want.
I.e. it plays the input directly out as it comes in.
来源：https://stackoverflow.com/questions/8076850/mic-input-to-the-speaker-output-on-an-ios-device