Sidekick VS ContactMonkey

SalesLoft - The simpliest way to build the most accurate and targeted lists of leads on the internet

ReadNotify - ReadNotify enables the user to know when email is sent and the reciever reads the email.

Yesware - Sell smarter with email tracking and more

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.

Streak - Manage customers inside Gmail

GetNotify - GetNotify is a free email tracking software solution.