title: What is this big number for backgroundTimeRemaining
body: <p>I have just entered into iOS programming and am struggling with many things. </p>
  
  <p>I am trying to implement small piece of code to getting current location and send it to server in the background.
  When I call <code>beginBackgroundTaskWithExpirationHandler</code>, I found that <code>backgroundTimeRemaining</code> property returns so big number. Look at the log below the code.</p>
  
  <pre><code>if (self.backgroundTask == UIBackgroundTaskInvalid) {
          NSLog(@"***** startBackground work");
  
          UIApplication *app = [UIApplication sharedApplication];
  
          self.backgroundTask = [app beginBackgroundTaskWithExpirationHandler:^{
              NSLog(@"Background handler called. Not running background tasks anymore.");
              [app endBackgroundTask:self.backgroundTask];
              self.backgroundTask = UIBackgroundTaskInvalid;
          }];
  
          DebugLog(@"====&gt;backgroundTimeRemaining:%.1f seconds", app.backgroundTimeRemaining);
          if (timer == nil) {
              timer = [NSTimer scheduledTimerWithTimeInterval:10 * 60
                                                       target:self
                                                     selector: @selector(timerFired:)
                                                     userInfo:nil
                                                      repeats:YES];
          }
      }
  </code></pre>
  
  <p>Log:</p>
  
  <pre><code>2013-11-29 09:23:14.852 JeeneeLocatorService[1666:70b] &lt;JLSViewController.m:(317)&gt; ====&gt;backgroundTimeRemaining:179769313486231570814527423731704356798070567525844996598917476803157260780028538760589558632766878171540458953514382464234321326889464182768467546703537516986049910576551282076245490090389328944075868508455133942304583236903222948165808559332123348274797826204144723168738177180919299881250404026184124858368.0 seconds
  </code></pre>
  
  <p>It does not look normal and I have read from iOS developer library site iOS allows about 10 minutes even though I call 
  <code>beginBackgroundTaskWithExpirationHandler</code> to do long time background task.</p>
  
  <p>I am testing with iOS7 simulator in XCode5. Is it true that I can have that much of time for background job. Your answer would be very appreciated.</p>
  
  <p>EDIT:
  After getting answer, I move the remaining time display code into the timerFired: method.</p>
  
  <pre><code>- (void)timerFired:(NSTimer *)timer {
          DebugLog(@"***** Timer fired *****");
  
          UIApplication *app = [UIApplication sharedApplication];
          DebugLog(@"====&gt;backgroundTimeRemaining:%.1f seconds", app.backgroundTimeRemaining);
   }
  </code></pre>
  
  <p>But, it still gives me same time left whenever timerFired: method is called. Does not this work just in simulator?</p>