title: Dynamic first View Controller in iOS
body: <p>I am having a little chicken/egg problem in understanding how the first view controller is chosen, and how it can change dynamically.</p>
  
  <p>In a typical login based application (e.g. facebook) you have a first view controller that's the login. Once you've logged in, another view is first the next time you enter the application.</p>
  
  <p>I can't see one place (in main.m?) or the app delegate where you can choose the first view and apply some logic to choosing it. What I have seen, is how a first view is used anyway, and within that view some logic is done whether or not to invoke the login window. Is that the only practice to get this done? I don't want my main view flashing for a moment before it spawns a login view in case the user needs to login. Can't I just go directly to the login view if needed, or to the 'logged in' view first, if the user is already logged in?</p>