Object slide like ice without collision


I have a GameObject wich move when we moved one finger on the screen with this script:

if(Input.touchCount > 0 && Input.GetTouch(0).phase == TouchPhase.Moved) {
		touchDeltaPosition = Input.GetTouch(0).deltaPosition;
        touchDeltaPosition.y*speed, 0);

Now i would want if I remove my finger to the screen and i moved my finger fast, the GameObject continue this run with deceleration to a stop but not if i move it slowly.

Any ideas how to do this?

If I understand your question correctly, all you are looking for is Velocity?

position += velocity * dt;