ToneGenerator
A simple example of tone generator using AVAudioPlayerUnit
Created by OOPer in cooperation with shlab.jp, on 2015/3/22.
Inspired by this article http://www.cocoawithlove.com/2010/10/ios-tone-generator-introduction-to.html .
=========================================================================== BUILD REQUIREMENTS:
Xcode 8.3.3, iOS SDK 10
===========================================================================