
Description: Postbox is an email client for Windows and macOS that provides a clean, easy-to-use interface for managing multiple email accounts. It supports POP3, IMAP, Exchange, Gmail, Outlook.com, Yahoo and more.
Type: Open Source Test Automation Framework
Founded: 2011
Primary Use: Mobile app testing automation
Supported Platforms: iOS, Android, Windows

Description: Spicebird is a free, open source email and calendar suite that includes email, contacts, and calendaring. It works with existing email accounts and calendars and is available on Windows, Linux and Mac.
Type: Cloud-based Test Automation Platform
Founded: 2015
Primary Use: Web, mobile, and API testing
Supported Platforms: Web, iOS, Android, API