Mailtrack.io - The best email tracking solution I've found. Free
ReadNotify - ReadNotify enables the user to know when email is sent and the reciever reads the email.
GetNotify - GetNotify is a free email tracking software solution.
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.
WhoReadMe - WhoReadMe is an email tracking solution that provides details on read duration, recipient location, organization name, operating system etc.
EmailGreen - EmailGreen is a web-based email marketing and comprehensive CRM solution that is created to help organizations and companies manage their contacts and execute all the valuable campaigns as well as optimize social media channels among other so they c…