title: Apple Watch display sleep pauses NSTimer, but WKInterfaceTimer keeps counting down
body: <p>As per Apple documentation, one will use both a WKInterfaceTimer (local to Watch, counts down but does not trigger any event when ends) and an NSTimer (to trigger methods when timer ends). So, I have both an NSTimer and a WKInterfaceTimer in my App Interface Controller. On the Simulator, on all schemes when the WatchApp runs, the NSTimer &amp; the WKInterfaceTimer keep counting down (as they should) when the Watch is either in awake or sleep mode (using the Simulator Lock/Unlock, as instructed in Apple's manual).</p>
  
  <p>However, on the real physical Watch, the 2 timers behave differently upon the Watch display sleep (blackout) and awake states. The sleep mode PAUSES the NSTimer of the Interface Controller, but the WKInterfaceTimer keeps counting down (as it should). </p>
  
  <p>So, the 2 Timers run out of synch immediately upon the first physical Apple Watch sleep (NSTimer pauses, WKInterfaceTimer keeps counting down). Seeking others experiences and whether someone implemented a good way to keep both NSTimer and WKInterfaceTime in synch regardless of the Watch mode (sleep or awake).</p>