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
ActiveCampaign - Integrated email marketing, marketing automation, and small business CRM. Send beautiful newsletters, setup behavioral based automations, and benefit from sales automation.
ReadNotify - ReadNotify enables the user to know when email is sent and the reciever reads the email.
Pardot - Salesforce B2B marketing automation
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.