
Description: Poste.io is an open-source newsletter service that allows users to easily create, send, and manage email newsletters. It has a simple drag-and-drop editor to design newsletter templates and customizable subscription forms to grow mailing lists.
Type: Open Source Test Automation Framework
Founded: 2011
Primary Use: Mobile app testing automation
Supported Platforms: iOS, Android, Windows

Description: WildDuck is an open-source email server that focuses on security, privacy, and ease of use. It supports standard email protocols like IMAP, POP3, and SMTP and has features like spam filtering, aliases, autoresponders, and more.
Type: Cloud-based Test Automation Platform
Founded: 2015
Primary Use: Web, mobile, and API testing
Supported Platforms: Web, iOS, Android, API