The simple way to create mails

Monitors the delayed_job queue and periodically tests its ability to deliver e-mail messages and e-mails you if something goes wrong, such as the delayed_job process crashes or one of its jobs fails or takes too long to complete.

Mailspy allows for quick and easy creation, sending and tracking of email campaigns

Postman Pat is a Private Mail/Messaging system for users on a webapp. It works in almost the same way as Facebook's private mail system.

A mass mailing tool for real threads aficionados

Permite sincronizar automaticamente seus modelos com o Mailee.me, inclusive com gerenciamento de optin.

Allows you to set up a second email to the form submitter that differs from the email sent to regular mail receiver.

Ruby wrapper library for GNU Mailman's admin functions

Ruby Gem for mailaddress verification

Learn with Mailbox

Generate email documentation from your mailer-specs.

Lita handler for interacting with mailgun.com

Gem that sends mail in case of resque job failure

Ruby Library for the mailboxlayer API, a web service that email validation & verification, https://mailboxlayer.com/

A ruby library for Mailchimp API V3.0 for manage lists.

Pop3 and MailDir is supported at the moment.

Async mailer without any painful setup

Use AppMail with the Ruby mail gem

A Rails mail delivery method using Iron MQ & Workers

This gem allows you to mock out your mailers, and set expectations on the messages that should be created and delivered.