FunnelBake Inbox Marketer is a free, easy-to-use app that lets you track all of your emails and get real-time notifications. In other words, you will know instantly when someone has read your emails or not. It's the best way to get your emails into the hands of the people who are actually going to read them.

When you install it, you will instantly get a double checkmark on your Gmail Account which indicates that the person has read your email.

What does it do?

Inbox Marketer for Gmail provides you with an intrusive dashboard that will show you all the details about the emails you have sent and the people who have read them. In addition, it allows you to track attachments for free.