HubSpot - Grow Better With HubSpot: Software that's powerful, not overpowering. Seamlessly connect your data, teams, and customers on one CRM platform that grows with your business.
Mailtrack.io - The best email tracking solution I've found. Free
MailChimp - MailChimp is the best way to design, send, and share email newsletters.
ReadNotify - ReadNotify enables the user to know when email is sent and the reciever reads the email.
Marketo - Marketo's powerful marketing automation software helps marketers master the art & science of digital marketing to engage customers and prospects.
Bananatag - Find out what happens to your emails after you press send! Add email tracking, attachment tracking, email scheduling and templates to your daily emails.