title: NSTimer and performing a selector on the main thread
body: <p>Is it possible to run a selector which is invoked by the nstimer on the main thread?</p>
  
  <p>The NSTimer is spawned in it's own thread.</p>
  
  <p>My structure is that a thread invokes a method with a nstimer, the nstimer invokes a method that do some updates, but I need these updates to happen on the main thread. What is the solution? Add another method and say <code>performOnMainThread</code>?</p>