Input.touchCount

Description

Number of touches. Guaranteed not to change throughout the frame. (Read Only)

function Update () {
    if (Input.touchCount > 0) {
        print(Input.touchCount);
    }
}

using UnityEngine;
using System.Collections;

public class ExampleClass : MonoBehaviour {
    void Update() {
        if (Input.touchCount > 0)
            print(Input.touchCount);
        
    }
}