This is a Perfect Viewer plugin. Let Perfect Viewer support PDF & DJVU file. To use this plugin you must install Perfect Viewer ver 1.7+ first. *Attention! please make sure Perfect Viewer is not running before install the plugin. Or you can reboot your device after install the plugin. This plugin is license under GPL V3 Source code can download from http://code.google.com/p/perfect-viewer-pdf-plugin/