
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: PDF Expert is a PDF reader and annotation tool for Mac. It allows you to view, edit, annotate, sign, and fill PDF documents. Key features include tabbed browsing, annotation tools, OCR text search, encryption support, digital signatures, and form filling.
Type: Cloud-based Test Automation Platform
Founded: 2015
Primary Use: Web, mobile, and API testing
Supported Platforms: Web, iOS, Android, API