Out of all the email sending companies this one still holds true to being the best. Not only does it do all the tracking like the others but the custom emails based on website actions is what makes this unique. That and the fact you don't get billed some crazy amount for emails sent, you are billed based on the number of customers/emails you have not by the number of emails you send out.
https://www.activecampaign.com/
Track emails sent from Gmail, know when someone opens your emails and if they click links within your emails. Great tool that makes Gmail even better: