What would be the class responsible for call answering screen.
I think it's a private framework, or even the SpringBoard.
But the SpringBoard has dozens of classes, and as I have access only to the header, it is difficult to know what the caller display phone service.
Does anyone know what class and method to the caller?
There are two classes responsible for that (one for Phone call and second for facetime) in /System/Library/SpringBoardPlugins/IncomingCall.servicebundle/IncomingCall plugin
MPIncomingFaceTimeCallController
MPIncomingPhoneCallController
and -(id)newBottomBar
selector.
The another way is writing a plugin for iEnhancer which deals with it, I can provide you plugin SDK.