If you've downloaded the Maps and Apps Gallery code and done some additional configuration you can host your configuration of the Maps and Apps Gallery application in your organization.

To share a group using your edited configuration of Maps and Apps Gallery, create a new application template item in your organization that points to Esri's code for the app. Apply your configuration to this new app template and share it with your organization's Gallery Applications group. Members of your organization can now share groups using your edited Maps and Apps Gallery app template.

Locate the existing app template

Your configuration will be applied to an existing template, and the new application item you will create must reference the location of the existing application code.

To locate an existing template, complete the following steps:

1. Sign in to Portal for ArcGIS, ArcGIS Enterprise, or your ArcGIS Online organization.
2. Go to the Gallery and change the view to Esri Featured Content.
3. In the filters on the left side of the gallery click Apps > Configurable Apps and open the Details page for the Maps and Apps Gallery app.
4. Find the Properties section and copy the URL to application code.

Create a new app item

Create a new item in ArcGIS Online that points to Esri's application code, but uses your edited configuration parameters.

To add a new app item, complete the following steps:

1. Add an item and configure the item as a JavaScript application that is Configurable for Web Mapping.
2. When asked for the application URL, use the URL copied from the application description. This URL will likely change as you interact with this dialog; this is ok for now but will need to be fixed later.
3. Add a title and tags that describe the modifications you've made to the configuration. Keep in mind that this item is the template that will be available in the Make a Web Application gallery, not the final application that will display your map.
4. Once the item has been created, edit the item's details and fix the URL property. The title, thumbnail, summary, description, access and use constraints, tags, and credits can also be updated.
5. Copy the contents of your modified configuration file into the Configuration Parameters text box and click the Save button.

Add the item to your template gallery

To share group content using your new template, the template must be accessible in the Make a Gallery Application gallery. These steps may require Administrative access to the organization.

To add the new template item to your organization's Gallery Application gallery, complete the following steps:

1. Confirm that your organization uses a custom Gallery Applications group by browsing to Organization > Edit Settings > Groups. If the value of the Gallery Applications setting is Esri Default, create a new group, then change this setting to point to your new group.
2. Share your new gallery application item with your organization's Gallery Applications group.

Now when members of your organization create an app from a group, your edited application template will appear in the application gallery.