MediaFunnel - MediaFunnel supports multiple users on one or more Twitter Accounts or Facebook Pages.
Flexmail Solution - Professional email marketing with powerful and easy-to-use features
Mandrill - Mandrill is a new way for apps to send transactional email. It runs on the delivery infrastructure that powers MailChimp.
Mizmoz - Easy-to-use, state of the art, email service provider dedicated to support growing businesses.
SocialReplay - SocialReplay: Daily snapshot of your social media accounts. For Professionals - From $5/month
Marble Responsive Email Designer - Marble helps you design beautiful and mobile-friendly emails and newsletters.