
Description: Okular is a versatile document viewer software for KDE. It supports viewing PDFs, EPUBs, ODT, and other document formats. Okular allows annotating, highlighting, commenting on documents as well as filling forms.
Type: Open Source Test Automation Framework
Founded: 2011
Primary Use: Mobile app testing automation
Supported Platforms: iOS, Android, Windows

Description: MJ PDF Reader is a free, lightweight PDF viewer for Windows. It allows you to view, print, and annotate PDF documents. Key features include tabbed browsing, search, bookmarks, and basic annotation tools.
Type: Cloud-based Test Automation Platform
Founded: 2015
Primary Use: Web, mobile, and API testing
Supported Platforms: Web, iOS, Android, API