Boomerang for Outlook - Boomerang for Outlook offers email productivity tools to track, schedule and send mails at the right time.
EmailTrackerPro - EmailTrackerPro is an email tracking and spam filter solution.
Outlook4Gmail - Outlook4Gmail provides easy synchronization of your Outlook and Google accounts
ReadNotify - ReadNotify enables the user to know when email is sent and the reciever reads the email.
Covideo - Covideo is a Video Email Platform for Businesses that enables companies to communicate quickly and effectively with their customers.
Sendia - Send cold email in seconds with Sendia, an outreach tool for Gmail that's free & easy to use!