title: applicationWillResignActive impact on application?
body: <p>I am writing an application that records a users position at regular intervals whilst walking. I am using an NSTimers to schedule "startUpdatingLocation" followed by calling "stopUpdatingLocation" shortly afterwards to save as much battery as possible. </p>
  
  <p>I want the user to be able to start the application and lock the phone thereby putting the application in an inactive state. My question is when this happens my application (when running via Xcode) seems to continue as normal, but I am curious if there are any differences in the way the application runs in this state as apposed to when the application is running as active?</p>
  
  <p>From the docs it only mentions "applicationWillResignActive" with regards to the application passing through that state on its way to the background. I am more interested in how an application behaves when a used locks the UI and puts the phone away, I just want to make sure its going to keep doing what it should be doing or do I need to take extra measures?</p>