title: Swift: download and open pdf file
body: <p>Excuse me if it's a stupid question but I didn't find an answer: what's the default pdf reader in iPhone? Is it iBooks for all iPhones? I ask about this because in my swift application I want to download a pdf file then open it by the default pdf reader (or another application) of the device. Still now I can do that with to ways: the first is when the button "Download" is tapped, I let the user choose the way of downloading the file via <code>UIDocumentInteractionController</code> then he can import it using iBooks, Documents, Chrome... I tested it and it works perfectly. The second way is to download the file inside the application (I got the example from the answer of this <a href="https://stackoverflow.com/questions/29479812/saving-pdf-files-with-swift-in-ios-and-display-them">question</a>) then open it by a pdf reader (the default native one if this is possible). </p>
  
  <p>Any suggestions please?</p>