title: How to prevent multiple location notifications from being triggered
body: <p>I have multiple location notifications registered, often they overlap with each other. I want to limit to one fired notification per day, but the problem is that I do not have any way to cancel all the pending notifications when app is killed and can only do it when BGAppRefreshTaskRequest is triggered (which is not a common thing most of the times). And the worst part is that if user is in overlapping area he'll receive multiple push notifications at once. </p>
  
  <p>Code to register notification:</p>
  
  <pre><code>let content = UNMutableNotificationContent()
  content.title = "Title"
  content.body = "Body"
  content.sound = .default
  content.userInfo = ["locationNotificationId" : id]
  content.categoryIdentifier = "geofenceNotifications"
  
  let region = CLCircularRegion(center: location,
                                radius: CLLocationDistance(range),
                                identifier: id)
  region.notifyOnEntry = true
  region.notifyOnExit = false
  let trigger = UNLocationNotificationTrigger(region: region, repeats: false)
  
  let request = UNNotificationRequest(identifier: id,
                                      content: content,
                                      trigger: trigger)
  
  UNUserNotificationCenter.current().add(request, withCompletionHandler: { error in
      if let error = error {
          print(error)
      }
  })
  </code></pre>
  
  <p>What do I do to prevent other notifications being triggered after one is fired if app is in the background or killed?</p>