Audio spectrum analyzer

Question

I want to make an android app(Java based) with sound spectrum analyzer which analyzes the sounds that are playing right now in another app (music player for instance).
How is it possible to do?

P.S. Not from a microphone!
Thank you :)

Answer 1

Now this is some high level stuff. But I love the way how people are coming up with questions related to electrical engineering field and want to solve them using code.