
Description: Gaaiho PDF Reader is a free, open-source PDF viewer for Windows. It provides a simple, no-frills interface for viewing, printing, and annotating PDF documents. Key features include tabbed browsing, bookmarking, basic markup tools, and smooth scrolling/zooming.
Type: Open Source Test Automation Framework
Founded: 2011
Primary Use: Mobile app testing automation
Supported Platforms: iOS, Android, Windows

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: Cloud-based Test Automation Platform
Founded: 2015
Primary Use: Web, mobile, and API testing
Supported Platforms: Web, iOS, Android, API