I created a Web App and shared it publicly. When I went to test it, it wants me to log into my AGOL. Not sure what is going on.
You should check if the webMAP is shared publicly.
Are you an organizational AGOL acct user and does your URL start with https://?
If so, replace https://<your organizational prefix>.arcgis.com with www.arcgis.com
That worked for us. Instead of sending folks URLs beginning with https://unc.maps.arcgis.com/whatever URL , we sent them ones beginning with www.arcgis.com/whatever URL and prompt for login went away.
Some of the Web Apps are using features or tools that will actually consume Online credits. For example, Analysis widget, Direction widget require you to log in to your Online account when you open them. So that public can't consume you Org's credits by using them.
Please make sure that you don't expose such tools to the public.
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