A SharePoint 2013 document toolbar button for PDF files that will open them directly in a client application (like Adobe Acrobat Reader) rather than the browser.
When working with PDF files in SharePoint, most of the time these have to be opened in the browser and most of the time that works. That is because an Adobe plugin within your browser checks if the file which is returned has a content type of application/pdf and if so, it opens the document within your browser.
For some users this was not what they wanted. The wanted the option to open multiple PDF documents and show them next to each other on their screen (not in different browser windows). You can disable the Adobe browser plugin, but this will impact all PDF’s you download, also from other sources (Internet etc.)
Through this SharePoint 2013 document toolbar button for PDF files it will open them directly in a client application (like Adobe Acrobat Reader) rather than the browser.