Startup Around - Quick startup content every 30 minutes from 100+ publishers
Mailtrack.io - The best email tracking solution I've found. Free
Supscrib - The new way of subscribing to newsletters
ReadNotify - ReadNotify enables the user to know when email is sent and the reciever reads the email.
Morning Reader - Curated technology and blockchain news
GetNotify - GetNotify is a free email tracking software solution.