Strike - Share your experience and hold businesses accountable 👊
ReadNotify - ReadNotify enables the user to know when email is sent and the reciever reads the email.
dip - accountability groups for developers
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.
Rainmaker - Rainmaker allows you to make your Google Contacts better.
Intelliverse Email Tracker - Intelliverse Email Tracker provides insights to increase the productivity of your emails.