Multi touch (help have issues)

i’m having some problems with this next stage that i’m on. I have been using MouseButtonDown but i can only pop one ball at a time. i have been looking up on multi touch and what they say just goes over my head multi touch 4 loop and hit test? i am having trouble understanding the code to go with it. what i need to happen, instead of one touch i need two at the same time. i want to know if i can keep the OnMOuseDown or if i need to change it up, also ready using a raycast? not a big fan of rays if you guys could help me i would really appreciate it!

CODE: THIS CODE IS PLACE ON THE BALLS THEMSELVES

#pragma strict
var tapCount : int;
var Health : int;
var bubbleEasy : boolean = false;
var bubbleMed : boolean = false;
var bubbleHard : boolean = false;




function start()
{
if (bubbleEasy == true){

	Health = 1;
}
else if (bubbleMed == true){

	Health = 2;
}		
else if (bubbleHard == true){

	Health = 3;
}
}

function Update(){

if (Health == 0){
   
   PopBubble();   
}
}



function OnMouseDown()
{
	Health -= 1;
	
	//Destroy (gameObject);
}


function OnDestroy (){

tapCount += 1;

}

function PopBubble(){

Destroy (gameObject);




}

figured it out.