Pointofmail.com - Know who, when and where read, clicked and forwarded your email.
Outreach - Outreach Is Your Sales Communication Platform
ReadNotify - ReadNotify enables the user to know when email is sent and the reciever reads the email.
SalesLoft - The simpliest way to build the most accurate and targeted lists of leads on the internet
MailChimp - MailChimp is the best way to design, send, and share email newsletters.
Yesware - Sell smarter with email tracking and more