For test purposes I'd like to use applications and widgets from ArcGIS f. Developer in Story Map Journal. From what I've learned it is not possible to use customized apps in AGOL so I would modify and download the sandbox code (as html file), upload it to my webserver and access the map-application through a webmap / iframe container in the main stage.
Is there any way to improve this workflow? Will the web application builder be of any use?
How will users be authenticated, as my app is not registered with AGOL?