Great
It's free and very useful, but the rotations need to be improved because it makes exploring hard. There is one single rotation axis: the longitudinal axis of the body. If you zoom in and try rotating, instead of the rotation being done on the same spot you are on with an imaginary axis longitudinal of the middle of the screen, it will rotate with the longitudinal axis of the body. Beside that, If you rotate circular it will also rotate the body circular which is really not needed, you end up rotating the body upside down by mistake. Zooming in and out is also very rigid and slow.
