Sound Game (Sound Wave)

I want to create a android game where you have to follow a sound wave with your finger. Its something like Mmm fingers but you have to follow the sound wave. Like when there is a hight tone the sound wave goes left and when there is a low tone the souns wave goes right. The game would be played in portrayed mode. I dont know how to make the sound wave :/ . I tried some solutions but none worked :/

 

Where does the sound come from that generates a wave? Microphone? A sound file?