Mobile Locker uses PDFTron to display PDF files
iOS can display PDF files natively, but it is not very good and can crash when opening complex PDFs.
Mobile Locker for iOS uses PDFTron library to display PDF files.
<!-- A direct link to a relative PDF will by opened by the PDF viewer. --> <a href="pdf/employee-handbook.pdf">Employee Handbook</a>
When the user taps that link, the app will intercept it and open that PDF in PDFTron: