
Description: Firefox PDF Viewer (PDF.js) is an open source PDF viewer that is built into Firefox. It allows you to view PDFs directly in the browser without needing an external plugin.
Type: Open Source Test Automation Framework
Founded: 2011
Primary Use: Mobile app testing automation
Supported Platforms: iOS, Android, Windows

Description: Haihaisoft PDF Reader is a free, lightweight PDF viewer and editor for Windows. It allows you to view, print, annotate, and fill out PDF documents. Key features include tabbed viewing, smart form fill, annotation tools, and security options.
Type: Cloud-based Test Automation Platform
Founded: 2015
Primary Use: Web, mobile, and API testing
Supported Platforms: Web, iOS, Android, API