title: performSelector:afterDelay versus NSTimer:ScheduleTimerWithTimeInterval
body: <p>I have a method I would like to execute (non repeating) after a time delay.</p>
  
  <p>I could use performSelector:afterDelay or I could schedule an NSTimer and specify the selector as a parameter to that.</p>
  
  <p>What are the advantages / disadvantages of using one over the other if the end result is the same (which is that my method will be called after the specified time delay). 
  Is it not matter which one I use?</p>
  
  <p>(In case it is relevant, my method will get called both in the foreground and when the app moves to the background during the 10 minute window available via beginBackgroundTaskWithEcpirationHandler).</p>
  
  <p>TIA</p>