From space to touch

Unity Engine
1

Hey Guys
This might be a easy question, but i dont get how to change it…
With this script i can jump while pressing space…

How do i change this to a simple touch to jump?
Here is the script:

using UnityEngine;
using System.Collections;

public class runnerscript : MonoBehaviour {

	public float Acceleration = 10;
	public float maxSpeed = 10;
	public Vector3 jumpVelocity;

	private bool touchGround = false;

	void Update () {
						
		if (touchGround  Input.GetButtonDown ("Jump")) {
			rigidbody.AddRelativeForce (jumpVelocity, ForceMode.VelocityChange);
			touchGround = false;
		}

		var curSpeed = rigidbody.velocity;
			curSpeed.y = 0;

		if (touchGround  curSpeed.magnitude < maxSpeed) {
		rigidbody.AddRelativeForce (Acceleration, 0, 0);
		}
	
	}
		void OnCollisionEnter(){
				touchGround = true;

		}
}
2

Change the Input.GetButtonDown for this

if (Input.touchCount > 0  Input.GetTouch(0).phase == TouchPhase.Began) {
		//dostuff
}