Apps similar to Adobe Acrobat PDF Extension include Firefox PDF Viewer (PDF.js), which is free and open source. Other options are Chrome PDF Viewer Plug-in. Between them they cover Mac, Windows and Linux.
PDF Viewer (aka pdf.js) is a new revolutionary extension using web standard technologies that allows you to display within Mozilla Firefox almost all PDF files found on the web without a plugin.
United States
In version 8, Google Chrome introduced a free PDF viewer, installed by default. While this plug-in lacks many features of the Adobe Acrobat Plug-in, it is much faster and lighter, and updates with the browser rather than an external utility.
United States
