title: What is the crash of "The app's Info.plist must contain an NSPhotoLibraryAddUsageDescription"?
body: <p>I faced the following error (iOS 11):</p>
  
  <blockquote>
    <p>This app has crashed because it attempted to access privacy-sensitive
    data without a usage description.  The app's Info.plist must contain
    an <code>NSPhotoLibraryAddUsageDescription</code> key with a string value
    explaining to the user how the app uses this data.</p>
  </blockquote>
  
  <p>Note that although the application <em>info.plist</em> does contains <code>NSPhotoLibraryUsageDescription</code> it still crashes, why?</p>