What are good services for hosting documents and images for embedding in ArcGIS Online?

[RiverCOG]

I am attempting to display preformatted documents on my ArcGIS Dashboard. 

https://rivercog.maps.arcgis.com/apps/dashboards/7bf627119e1747f8a6fc656dfdf9235b

By having the links in a feature they should change dynamically as the user picks which years' data they wish to view. It appeared that linking the embed code from SharePoint was going to work perfectly, but as usual SharePoint is useless if the public user is not also logged into 365.

Are there any recommended methods within the ArcGIS Online environment or possibly a trusted FTP service that would allow for hosting files that can be displayed to public viewers using Embedded Content in an ArcGIS Online Dashboard?

Thanks

[jcarlson]

We're on Amazon Web Services, and a public S3 bucket is great for this sort of thing. Our tax map browser, for example, uses feature attributes to populate parts of a URL.

https://kcgis-tax-maps.s3.us-east-2.amazonaws.com/2016/01-H_2016_line.pdf

You can take the concept a step further and create a CloudFront distribution from the S3 bucket, which would let you put the items in some custom domain, like "taxmaps.kendallcountyil.gov", etc. That uses Amazon's CDN, so folks viewing those documents will just be seeing a cached copy, and the number of GET requests (and thus costs) going to your bucket will be reduced. Could be worth doing if you anticipate a lot of traffic on this thing, as direct requests to a bucket can add up over time.