Scroll Wheel Replacement for Touch Screen(Android)

I have a script that is edited from the original MouseOrbit.js in Unity, to include zooming with the Scroll Wheel, Below:

Code (csharp):

1. var target : Transform;
2. var distance = 10.0;
3. var cameraSpeed = 5;
4.  
5. var xSpeed = 175.0;
6. var ySpeed = 75.0;
7.  
8. var yMinLimit = 20; //Lowest vertical angle in respect with the target.
9. var yMaxLimit = 80;
10.  
11. var minDistance = 5; //Min distance of the camera from the target
12. var maxDistance = 20;
13.  
14. private var x = 0.0;
15. private var y = 0.0;
16.  
17. function Start () {
18.     var angles = transform.eulerAngles;
19.     x = angles.y;
20.     y = angles.x;
21.  
22.    // Make the rigid body not change rotation
23.       if (rigidbody)
24.       rigidbody.freezeRotation = true;
25. }
26.  
27. function Update () {
28.     if (target  camera) {
29.  
30.    //Zooming with mouse
31.    distance += Input.GetAxis("Mouse ScrollWheel")*distance*-1;
32.    distance = Mathf.Clamp(distance, minDistance, maxDistance);
33.  
34.    //Detect mouse drag;
35.    if(Input.GetMouseButton(0))   {
36.    
37.         x += Input.GetAxis("Mouse X") * xSpeed * 0.02;
38.         y -= Input.GetAxis("Mouse Y") * ySpeed * 0.02;      
39.       }
40.       y = ClampAngle(y, yMinLimit, yMaxLimit);
41.              
42.         var rotation = Quaternion.Euler(y, x, 0);
43.         var position = rotation * Vector3(0.0, 0.0, -distance) + target.position;
44.          
45.    transform.position = Vector3.Lerp (transform.position, position, cameraSpeed*Time.deltaTime);
46.       transform.rotation = rotation;      
47.     }
48. }
49.  
50. static function ClampAngle (angle : float, min : float, max : float) {
51.    if (angle < -360)
52.       angle += 360;
53.    if (angle > 360)
54.       angle -= 360;
55.    return Mathf.Clamp (angle, min, max);
56. }

Like I said there is nothing wrong with it but i would like to use it on an Android device to control the camera around a simple 3D object, for people to get a closer look at some of my work, i would like to find a way to scroll on the Android Touch Screen, By either placing a simple GUI Slider for zooming or actually Changing the script to allow a "Pinch" for zooming.

A "Pinch" Is placing two fingers on the touch screen, and sliding them together for zooming in or further appart for zooming out.

Please help.
Thanks.

PS: I am a n00b at this, dont hate me we were all there before.

 

let me know if you found a solution for this!