"Mouse Trap Boot" with touch screen not axis.

I basically have my code working the way i want. I can pull my boot back and when i release it kicks. But the issue i am having is getting it to work on an android touch screen instead of the horizontal axis. Any help would be greatly appreciated.

[code]using System.Collections;

public class Boot : MonoBehaviour {

 public Vector2 touchDeltaPosition;
 public Vector3 eulers;
 public float force = 410.0f;
 public float velocity;
 public GameObject pivot;
   
 public float speed = 0.1f;
 
 void Awake() {
 }
 
 // Use this for initialization
 void Start () {
 }
 
 
 // Update is called once per frame
 void Update () {
     
     
     if (Input.touchCount > 0 && Input.GetTouch(0).phase == TouchPhase.Moved) {
         touchDeltaPosition = Input.GetTouch(0).deltaPosition;
     } 
     
     velocity = Input.GetAxis("Horizontal") * 90;
     //velocity = touchDeltaPosition.x;
     
     Debug.Log(velocity);
     
     TapSelect ();
 }
 
 void TapSelect() {  

     if(velocity < 0) {
         pivot.transform.rotation = Quaternion.Euler(new Vector3(0, 0, velocity));
     }
     
 }
 
 
 
 void OnCollisionStay(Collision collision) {
     if (collision.rigidbody){
         Debug.Log("Collision: " + collision + collision.collider.name);
         collision.rigidbody.AddForce(new Vector3(force * 10, force * 10, 0));
     }
     else {
         return;
     }
     
 }
 

} [/code]