The description gets a bit confusing about the arrow+angle. Could you perhaps rephrase? Including the code you're using might help. You touch the Frisbee from your 3/4 angle or what have you, move your touch and release. The speed is determined by the distance moved and the duration of the touch. You say, "the end position determines the angle of the Frisbee's direction..." but how exactly do you intend that to work? In your 3/4 view, the angle of your touch movement on the screen is going to be angled towards the ground or sky, but did you want this sort of angle to the movement?

You need a vertical and horizontal direction, but how did you want the movement in your 3/4 view to relate to these? If you want it 1:1 camera relative, you would simply generate your direction from the camera's Transform.

As far as the force to use, the solution you present doesn't feel like it is the correct approach. What happens when a Frisbee is thrown is that it moves with force in the relative forward direction (not constant) (release velocity) and the rotation of the forward angle is adjusted based on the curvature of the throw (centripetal force) + lift - wind resistance, etc. So you actually have two directions to worry about, the release direction and the direction of the centripetal force +/- drag and lift.

Thanks for replying.

I'm sorry if I was confusing. I am thinking of how to better explain this. the frisbee is just an example. the actual is just a sliding disc on a flat plane/level design.

When moved, the disc follows along the floor.

That said, the control is meant to allow the finger to touch the disc, and then flick it towards a direction, the disc then follows towards the direction of the flick.

The camera is positioned above the disc, pulled back and looking onto it. (somewhat looking over the shoulder)