Some time ago I mentioned a number of components for viewing PDF files including the iBooks like PDF reading component vfr/Reader.
Here’s an open source component you can easily embed into Swift and Objective-C based apps providing a PDF document viewer that builds upon the previously mentioned vfr/Reader.
M13PDFKit provides a styling similar to that of iBooks in iOS 7+, and utilizes collection views. The expected features such as page previewing, bookmarks, and the thumbnail view are all included.
Here are a couple of images showing M13PDFKit in action:
You can find M13PDFKit on Github here.
A great PDF viewing component.