Tracking emails opened in gMail

Question

I want to track when emails are opened in gMail and display it somewhere.

I don't want to use third party mail service.

I need to track this with something else while using Gmail API.

A colleague said there is a tool like Shiftmail or something.

Do you know any tool to track email sent via Gmail API?

I am not really sure of what you mean by "track email opens". Are you trying to get the messages that are already "read" and display them on an interface or are you trying to track the message hops when it is being sent and determine if it has been delivered or not? — Morfinismo
@Morfinismo, correct, I want to track when emails are opened and display it somewhere.. — j doe
I think there might be a way of doing this. You have to use Gmail API with a service account to get a list of a user messages and then check if the each message has the label "Unread" applied to it. If it doesn't, that means the email is already read. You will have to look at the documentation here developers.google.com/gmail/api/v1/reference/users/messages/… and here developers.google.com/gmail/api/v1/reference/users/messages/get — Morfinismo

Teyam Teyam · Accepted Answer · 2016-11-17T08:47:10

Do you know any tool to track email sent via Gmail API?

AFAIK, Official Gmail Blog have announced about an exciting change to how Gmail works wherein email providers track opens by inserting a small image–unique to each subscriber–into the email. When that image is loaded, we know the email has been opened.

Please check Open tracking in Gmail is now more accurate for more information regarding this change.
On the other hand, you may want to also check and see if Postmark - Tracking opens helps. Sending emails with open tracking enabled will embed an invisible pixel into your emails that allows Postmark to record information when the email is viewed. Please note, however, of the given limitations on the use of Postmark.

Is there an API to take advantage of Gmail's pixel caching?

I'm quite not sure if this is what you're looking for, but you may want to also check Tracking Pixel API. As mentioned,

Google Mail caches images which can cause your pixel to be cached and not fire on email open! To get around this, add a no-cache header to your emails and you should be good to go!