In this blog you will see how to save and publish an app in SharePoint Online list. I have automatically generated an app using PowerApps named EmployeesApp in a custom SharePoint Online list.
Save and publish an app
Navigate to EmployeesApp created in a custom SharePoint Online list.
Edit the app using PowerApps studio. Once the changes are completed, click File tab.
Click Save button.
Click Publish this version.
App is published successfully.