
Description: Sioyek is an open-source PDF viewer designed for reading scientific papers and academic journals. It provides advanced PDF features like synchronized dual-page view, sticky notes, highlights and annotations. Sioyek aims to offer a clutter-free interface for focused reading.
Type: Open Source Test Automation Framework
Founded: 2011
Primary Use: Mobile app testing automation
Supported Platforms: iOS, Android, Windows

Description: SumatraPDF is a free and open-source PDF, eBook, XPS, DjVu, CHM, Comic Book (CBZ and CBR) reader for Windows. It is lightweight, customizable, and supports many advanced PDF features.
Type: Cloud-based Test Automation Platform
Founded: 2015
Primary Use: Web, mobile, and API testing
Supported Platforms: Web, iOS, Android, API