Voice Changer Android App

I want a Real time Android Voice Changer during call. - During call user can change their voice at real time. - User can change their voice by going to the application. - User can also set their voice as default. - Voice should based on funny sound effects like Evil, Alien, Chipmunk, Robot, Slow, Helium, Deep, Reverse, Talk into Fan, Robot, Mouse and Echo effect, WOMEN's and MEN's voices and more. The hard part is that it has to change your voice WHILE making a phone call. - So either it is a running app on the background on the phone which does this or - You modify the open source android "dailer" app in such a way that it changes your voice when you speak. The dailer app can be found on multiple websites. (This solution probably only working for outgoing calls only) I don't know if above is possible and whether there is a better solution for making a app like this, but i'm off course open for suggestions. You should provide the app with resources like graphics, icons, sounds and others. I want the full source code . High graphical design is not neccesary, although it must have some basic design and layout.