How do I rotate using touch controls for top down game

I can figure out touch controls for side scrollers rather easy, however I'm doing a top down shooter game, and it's proving to be really difficult.

You can obviously go up, down, left, and right but I want you to be able to rotate and face that direction that you're traveling in, so you can shoot that way also.

So far "rotate clockwise/counter-clockwise" has lead to iffy results. Any ideas?

thanks!

Have you tried Rotate towards Touch.x/Touch.y ?

Or have a sprite move to Touch.x,Touch.Y, and then rotate towards sprite (obviously the sprite is invisible)