Dashboard and all content appears to be shared with everyone, but why do I have to be logged in to view it?
You may have some layers or the webmap that is used in the Dashboard not shared publicly. The dashboard however is shared to public but the items that are contained such as web map and the layers are required to be shared too.
I agree with Manish! I would double check to make sure that all the items that make up the Dashboard are also shared publicly. I've seen this issue a few times and typically its because one of the feature services aren't set to public.
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