This is an example taken from a site tutorial of Unity3D.
using UnityEngine;
using System.Collections;
public class TouchTest : MonoBehaviour
{
void Update ()
{
Touch myTouch = Input.GetTouch(0);
Touch[] myTouches = Input.touches;
for(int i = 0; i < Input.touchCount; i++)
{
//Do something with the touches
}
}
}
You can pick up the touch coordinates for the instance of Touch
which in the example is called myTouch
and see if they collide with the ball you have on the screen. This for
of the example is for you to iterate over the rings if more than one touch occurred at the same time.