Spinning Sphere/Globe IOS

hey im writing a spinning globe script for an IOS application that as you can guess spins a sphere around based on touch input. my problem is that it works really well in debug, but on the pad not so much.

in Debug i have nice smooth movement and you can click on a position on the globe and drag it in the Y axis making it spin, on the pad however it lerps the rotation a significant amount when i touch the globe, where as it should stay perfectly still till i move my finger like in debug.

any thoughts anyone has on whats wrong with my code is very much appreciated

 using UnityEngine;
 using System;
 using System.Collections;
 
 public class dragScript : MonoBehaviour {
     
     private Vector3 m_Speed;
     private Vector3 m_AvgSpeed;
     private bool m_Dragging = false;
     
     public float m_ModSpeed =1;
     public float m_ModRotationSpeed =3;
     
     public void OnMouseDown () {
         m_Dragging = true;
     }
     
     public void Update () {
         if (Input.GetMouseButton(0) && m_Dragging) {
             Debug.Log("HIT new drag");
             m_Speed = new Vector3(-Input.GetAxis ("Mouse X"), /*Input.GetAxis("Mouse Y")*/0, 0);
             m_AvgSpeed = Vector3.Lerp(m_AvgSpeed,m_Speed,Time.deltaTime * 5);
         } else {
             if (m_Dragging) {
                 Debug.Log("HIT decrease speed");
                 m_Speed = m_AvgSpeed;
                 m_Dragging = false;
             }
             Debug.Log("HIT Lerp");
             float i = Time.deltaTime * m_ModSpeed;
             m_Speed = Vector3.Lerp( m_Speed, Vector3.zero, i);
         }
         Debug.Log("HIT rotate");
         transform.Rotate( Camera.main.transform.up * m_Speed.x * m_ModRotationSpeed, Space.World );    
     }
     }