Google is shutting down its Inbox app on April 2. The same goes for the Google+ service too. The current users might be receiving the notification stating that the Inbox app will be going away on April 2. According to the users, the link redirects them to the official Google Gmail app.
Most of the time Google, uses the Inbox app to test several feature before they include it into the Gmail app. We have tried the Inbox app before and we personally prefer using the app. However, last year, Google made a huge overhaul to the Gmail app. Most of the Inbox features has been included inside the application.