Make an app that can change incoming/out-going voice to different gender from the caller/receiver. For example, when a man calls a woman, the woman should hear a women's voice(which is the man) and the man should hear a man's voice(which is the woman).
Basically, this app should communicate with a server, which can offer this kind of service. You can build a server if you know the voice changing algorithm, or you can call the web service of a server that offers this service.
There are several apps that can do out going voice changing, but without voice changing feature for incoming calls.
Tell me if you can make this app by detailing the ways you will implement it in proposal, especially how to make the incoming voice changing function.
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