You can permanently delete an app you own in Developer Hub. This page shows how to delete the app and what happens to it and its resources afterward.
Warning: Once an app is deleted, it is permanently removed from the stack or the organization it was installed in. To use the app again, you will have to install it again in the required stack or organization.
How to delete an app from Developer Hub.
What happens to an app and its resources after deletion.
To delete an app, perform the steps given below:

This will permanently delete the app and all its resources.
Note: Before deleting an app, remember to uninstall all the instances of that app from the respective stack.