Turns your iPhone into a simple DTMF decoder. Simply hold the iPhone's microphone near to a clear source of DTMF tones (telephone "Touch Tones") and it will display the numbers being dialed. The decoded digits are also placed into a text area from which you can copy them to the clipboard. See it in action here: https://www.youtube.com/watch?v=l_QD8KFCJPw Source code freely available: https://github.com/veghead/ios-dtmf-decoder