Android, Intercept Outgoing call Read DTMF tones

My Android Application works with IVR calls. User calls a number, Listens to IVR one of the options on IVR is to launch the application. What i am trying to do is, when user hears on IVR "Press 0 to Launch --- app" User presses 0 on the default on screen keypad The call hangs up and the application opens. I am able to hangup the call programatically but cant really intercept the DTMF tones to launch app. It is becoming a challenge to implement this simple feature in newer versions of anroid. Is it possible using even any hacky method to intercept DTMF tones passing through an active call? what could be possible ways i should look for to detect the DTMF tones beinng passed during an active call? Any help is highly appreciated.