Rotate camera with 2 fingers Android Touch

Hey Guys I need a little bit of help, I can zoom with 2 fingers I can move the camera with 1 finger but how to rotate the camera if I finger is moved on +y and other on -y.

here is a picture with more explination

What I want to know is how to take, or how to see if the finger are not moving this way ← ->, but rather as in the picture

Read the answer by robertbu to this question: Twist to rotate

And the code by OP in the question for touch related details.