Touch doesn't work in the DrawLine project...

Hey guys, i took this DrawLine project from:

http://www.theappguruz.com/tutorial/draw-line-mouse-move-detect-line-collision-unity2d-unity3d/

It works perfectly, but when i build it to android devices, and do the "tap" i get nothing.. i don't know why, the script is has "Input.GetMouseButtonDown(0)" so the touch should work. Here is the script (C#).

 using UnityEngine;
 using System.Collections;
 using System.Collections.Generic;
 
 public class DrawLine : MonoBehaviour 
 {
     private LineRenderer line;
     private bool isMousePressed;
     private List<Vector3> pointsList;
     private Vector3 mousePos;
 
     // Structure for line points
     struct myLine
     {
         public Vector3 StartPoint;
         public Vector3 EndPoint;
     };
     //    -----------------------------------    
     void Awake()
     {
         // Create line renderer component and set its property
         line = gameObject.AddComponent<LineRenderer>();
         line.material =  new Material(Shader.Find("Particles/Additive"));
         line.SetVertexCount(0);
         line.SetWidth(0.1f,0.1f);
         line.SetColors(Color.green, Color.green);
         line.useWorldSpace = true;    
         isMousePressed = false;
         pointsList = new List<Vector3>();
 //        renderer.material.SetTextureOffset(
     }
     //    -----------------------------------    
     void Update () 
     {
         // If mouse button down, remove old line and set its color to green
         if(Input.GetMouseButtonDown(0))
         {
             isMousePressed = true;
             line.SetVertexCount(0);
             pointsList.RemoveRange(0,pointsList.Count);
             line.SetColors(Color.green, Color.green);
         }
         else if(Input.GetMouseButtonUp(0))
         {
             isMousePressed = false;
         }
         // Drawing line when mouse is moving(presses)
         if(isMousePressed)
         {
             mousePos = Camera.main.ScreenToWorldPoint(Input.mousePosition);
             mousePos.z=0;
             if (!pointsList.Contains (mousePos)) 
             {
                 pointsList.Add (mousePos);
                 line.SetVertexCount (pointsList.Count);
                 line.SetPosition (pointsList.Count - 1, (Vector3)pointsList [pointsList.Count - 1]);
                 if(isLineCollide())
                 {
                     isMousePressed = false;
                     line.SetColors(Color.red, Color.red);
                 }
             }
         }
     }
     //    -----------------------------------    
     //  Following method checks is currentLine(line drawn by last two points) collided with line 
     //    -----------------------------------    
     private bool isLineCollide()
     {
         if (pointsList.Count < 2)
             return false;
         int TotalLines = pointsList.Count - 1;
         myLine[] lines = new myLine[TotalLines];
         if (TotalLines > 1) 
         {
             for (int i=0; i<TotalLines; i++) 
             {
                 lines [i].StartPoint = (Vector3)pointsList [i];
                 lines [i].EndPoint = (Vector3)pointsList [i + 1];
             }
         }
         for (int i=0; i<TotalLines-1; i++) 
         {
             myLine currentLine;
             currentLine.StartPoint = (Vector3)pointsList [pointsList.Count - 2];
             currentLine.EndPoint = (Vector3)pointsList [pointsList.Count - 1];
             if (isLinesIntersect (lines [i], currentLine)) 
                 return true;
         }
         return false;
     }
     //    -----------------------------------    
     //    Following method checks whether given two points are same or not
     //    -----------------------------------    
     private bool checkPoints (Vector3 pointA, Vector3 pointB)
     {
         return (pointA.x == pointB.x && pointA.y == pointB.y);
     }
     //    -----------------------------------    
     //    Following method checks whether given two line intersect or not
     //    -----------------------------------    
     private bool isLinesIntersect (myLine L1, myLine L2)
     {
         if (checkPoints (L1.StartPoint, L2.StartPoint) ||
             checkPoints (L1.StartPoint, L2.EndPoint) ||
             checkPoints (L1.EndPoint, L2.StartPoint) ||
             checkPoints (L1.EndPoint, L2.EndPoint))
             return false;
         
         return((Mathf.Max (L1.StartPoint.x, L1.EndPoint.x) >= Mathf.Min (L2.StartPoint.x, L2.EndPoint.x)) &&
                (Mathf.Max (L2.StartPoint.x, L2.EndPoint.x) >= Mathf.Min (L1.StartPoint.x, L1.EndPoint.x)) &&
                (Mathf.Max (L1.StartPoint.y, L1.EndPoint.y) >= Mathf.Min (L2.StartPoint.y, L2.EndPoint.y)) &&
                (Mathf.Max (L2.StartPoint.y, L2.EndPoint.y) >= Mathf.Min (L1.StartPoint.y, L1.EndPoint.y)) 
                );
     }
 }

Somebody can help me to get the android build work?

Thanks for the help!