title: iPhone app for calculating distance and speed
body: <p>I am creating an navigation based iPhone app. I want to calculate the distance and speed of the user moving. Now I am using <code>CLLocationManager</code> for this. But it not that much accurate. I am calculating the distance with the api <code>distanceFromLocation:</code>. And then it is divided by time for calculating the speed. The <code>CLLocation</code>'s property <code>speed</code> is not accurate. Is it possible to find distance and speed using accelerometer.<br>
  Please let me know which method have to be used in my case.</p>