title_body: iBooks - Cover Image Page
upvoted_answer: linear="no"
  
  
  is the attribute that prevents a file in the spine from appearing in iBooks. In your case, you would simply remove it from this line which appears in the content.opf file:
  
  &lt;spine toc="ncx"&gt;
  &lt;itemref idref="cover" linear="no"/&gt;