automatic phone call / call interception

开发者_如何学JAVAI'm looking since some time already for information on this topic, but I'm not able to find help and example code.

Does anybody know if it's possible to make a phone call using an Android app to intercept the call and play e.g. some message by using the text-to-speech (TTS) engine?

You do not have access to the in-call audio stream to be able to play back anything that the other side will pick up. The only thing that works, sort of, is to have the device in speakerphone mode, so your TTS played through the speaker might be picked up by the microphone.