
Description: MuPDF is a free, open source PDF viewer and toolkit. It is lightweight, fast, and cross-platform, supporting Windows, macOS, Linux, Android, and iOS. MuPDF allows you to view PDFs quickly and smoothly while using minimal system resources.
Type: Open Source Test Automation Framework
Founded: 2011
Primary Use: Mobile app testing automation
Supported Platforms: iOS, Android, Windows

Description: Xournal++ is a free, open-source notetaking and sketching software for Linux. It supports pen input and annotations on PDFs. Key features include sticky notes, rulers, page templates, shape recognition, and LaTeX support.
Type: Cloud-based Test Automation Platform
Founded: 2015
Primary Use: Web, mobile, and API testing
Supported Platforms: Web, iOS, Android, API