title: does iOS let the app finish what it's doing before being suspended?
body: <p>If you have something processing and the user presses the home button, does iOS let the app finish processing until it's finished? I have an NSTimer that calls a function every half second, and I want to know if iOS sort of freezes the app where it was, or if it allows the function to finish before suspending the app.</p>
  
  <p>Also does pressing the home button pause an NSStream, or does it close the NSStream.</p>