title: Xcode Base SDK: What is the easiest way to install multiple SDK versions side by side
body: <p>Alright what I noticed is that when I am developing against iOS 4.3, and I set my deployment target as iOS 4.1, I DO NOT get any kind of warning from the IDE about calls which are not supported in the minimum deployment target.</p>
  
  <p>For example, calling [CLLocationManager authorizationStatus] shows no warning, despite the fact that the documentation for authorizationStatus says it was implemented in iOS 4.2.</p>
  
  <p>I expect this would be a problem when wouldn't it?</p>
  
  <p>From what I understand the solution to this is to download multiple SDK versions, temporarily build against the SDK for your minimum version, but switch to the current SDK version in order to ship.</p>
  
  <p>If there is a better way to do this please advise. How can I get more options in Xcode under the "Base SDK" setting?</p>