Moving and object using touch controls

I’m trying to move a sphere on my phone. I have a way to drag the sphere using a mouse but now I’m trying to switch over the touch controls. With touch controls I could have more then one finger touching the sphere. How would I go about using only one touch to move the sphere?

Input.touches returns all distinct Touch events from the previous frame. Touch.fingerId will give you a unique ID for the duration of that touch.

If you only want to use the first touch in a drag, or the touch closest to the sphere etc, then just store the fingerId when a drag/touch event starts and filter out all other touch input until that touch event completes.