
Description: SMTPeter is an open-source email server software designed for small businesses and developers. It allows you to send, receive, and manage emails on your own servers with features like spam filters, email aliases, user management, and analytics.
Type: Open Source Test Automation Framework
Founded: 2011
Primary Use: Mobile app testing automation
Supported Platforms: iOS, Android, Windows

Description: Mailgun is an email service built for developers. It provides a powerful API that allows sending, receiving, and tracking emails easily from within an application. Key features are flexible APIs, scalable infrastructure, and deliverability optimization.
Type: Cloud-based Test Automation Platform
Founded: 2015
Primary Use: Web, mobile, and API testing
Supported Platforms: Web, iOS, Android, API