Listmonk - Send e-mail campaigns from a powerful dashboard. High performance and features packed into one app.

HelpRange - HelpRange lets you easily share documents and analyze their usage.

Mailman - Mailman is free software for managing electronic mail discussion and e-newsletter lists.

Dropbox DocSend - Dropbox DocSend is a secure file and document sharing solution that gives users analytics and control of document in their critical workflows. Key features include sending documents as secure links, eSignature, and customizable virtual data rooms.

Sendy - Sendy is a self hosted newsletter app that sends emails 100x cheaper via Amazon SES

Attach - Gain the insight and control you need to close more deals. Attach helps you understand how your customers interact with your content so you know how to time and tailor your follow up for maximum impact.