Inbox app by Google was released 4 years ago by Google. People who were using 3rd party apps instead of Gmail app tried it. Most of the users found it innovative and they liked it.
The reason for liking the app was because it was not Gmail app but yet developed by Google. Obviously there’s more to that.
However, Google has struggled to update the Inbox app.
They recently redesigned the Gmail app and added all the features that were in the Inbox app. It’s sad to say goodbye to an app for it’s long time users. It might be a good thing because Google will now focus on only one app.