title: "Builds for" option in interface builder
body: <p>There is an option "Builds for" in the file inspector of interface builder. I found that it affects attributes of deployment element in the XIB file. But I cannot find what is the real purpose of this setting.</p>
  
  <p>I have an iOS app with deployment target iOS7. I select an option "iOS 8.0 and Later" in the "Builds for" setting in one specific XIB. Then I launch the app on iPhone with iOS 7.1. but the screen defined by this XIB can be loaded and used. Does this setting have some impact on running application?</p>