Create a SharePoint App Catalog and Deploy an Add-in
A SharePoint Online tutorial by Peter Kalmström
Microsoft
has changed the behaviour in SharePoint Online, so now an
app catalog is automatically created the first time an admin
clicks on Apps >Open under 'More features' in the SharePoint
Admin center. It is now called Apps site instead of app
catalog.
An app catalog/Apps site is a type of site collection that
is used for storing web parts for your organization's internal
use. In the first demo below, Peter Kalmström shows with
steps and in a demo how to create an app catalog in SharePoint
Online.
Create an app catalog
(To perform these steps you must be a Global or SharePoint admin.)
Open the SharePoint admin center
Click on "apps" and then on the App Catalog link.
Keep the radio button selected for "Create a new
app catalog site" and click OK.
Microsoft
has changed the behaviour in SharePoint Online, so now an
app catalog is automatically created the first time an admin
clicks on Apps >Open under 'More features' in the SharePoint
Admin center. It is now called Apps site instead of app
catalog. 
