
Description: Lemon Group Messenger is a free and open-source instant messaging app for groups. It allows users to chat in groups up to 500 people, make voice and video calls, share photos, audio, video and other files securely. It works across platforms like Windows, Mac, Linux, Android and iOS.
Type: Open Source Test Automation Framework
Founded: 2011
Primary Use: Mobile app testing automation
Supported Platforms: iOS, Android, Windows

Description: Threema is a secure messaging app that emphasizes privacy and security with end-to-end encryption for all communications. It allows you to message and call other Threema users.
Type: Cloud-based Test Automation Platform
Founded: 2015
Primary Use: Web, mobile, and API testing
Supported Platforms: Web, iOS, Android, API