title: Which iOS frameworks most useful to learn and in what order?
body: <p>I've just started learning Obj-C and the Cocoa-Touch framework for developing iPhone and iPad applications. When you add a framework to an XCode project I can't help notice there are an enormous number to get familiar e.g. AddressBook, CoreData, Foundation, Security etc.</p>
  
  <ul>
  <li>Which frameworks are common to most
  projects and the most important to
  master i.e. UIKit?</li>
  <li>Which frameworks
  will require a prerequisite
  level of understanding of another? </li>
  <li>Which frameworks are application specific
  and can be left until needed i.e.
  Accelerate?</li>
  </ul>