Google has revealed it is closing down another one of its workplace apps, with its Inbox email service ending on April 2nd.

Inbox had been set for the chop for some time, with a Spring 2019 date named by Google last year, but users are now starting to be alerted to the end of their apps.

Some users reported yesterday seeing a pop-up screen that appears when they open the app, saying that the service will close in 15 days time - meaning Inbox could end on April 2nd.

The pop-up includes a link for the user to switch to the regular Gmail app, where they are assured their messages will be there waiting for them. Google also says it is "working hard" to continue porting over some of Inbox's most-loved features.

First announced in 2014 as an invitation-only service, Inbox offered a more interactive and intelligent way to access your emails away from the vanilla Gmail app. 

Praised for its Bundles feature, which brought emails of the same topic together, Inbox also inspired popular features such as automatically sifting through your messages, email snoozing and smart replies, and also featured the all-white design now seen on the main Gmail app.

Inbox is not the only Google service to face the final curtain soon, with the technology giant revealing its troubled Google+ social network will also be closing on April 2nd.

Despite huge internal backing, Google+ will close after two major bugs were detected in the service, with video call service Allo and URL shortener goo.gl also set to close.

As you might expect, the death of Inbox has made some people pretty unhappy. An online petition to stop Google from shutting down Inbox was created late last year and actually got a boost in signatures on Tuesday morning after the death notification went out. At the time of writing, it was about 500 signatures away from its goal of 10,000.

Inbox fans took to Twitter to mourn the outgoing app and vent their frustration.

In an official statement the company said, "Four years after launching Inbox in 2014, we've learned a lot about how to make email better-and we've taken popular Inbox experiences and added them into Gmail to help more than a billion people get more done with their emails every day. As we look to the future, we want to take a more focused approach that will help us bring the best email experience to everyone. As a result, we're planning to focus solely on Gmail and end support for Inbox by Gmail at the end of March 2019."