App Archiving
Last updated July 22, 2019
Some apps on Heroku may be automatically archived.
When archived, an app won’t be accessible via any web domain. In particular, accessing the app on its .herokuapp.com domain will yield a “No such app” response.
Currently apps are archived only if they have never had a user-initiated deploy, i.e. they are empty apps or apps created from templates and never changed.
Use the Heroku CLI to determine whether an app has been archived:
$ heroku apps:info -a example-app
=== example-app
Archived At: 2013-07-24 01:10 UTC
...
Apps can be un-archived by deploying any change to the application. See the getting started guides for details.