Hi, I've built a web mapping application using the web app builder. If I download the "code attachment" can I host this on my own web server? Alternatively, is there a way I can host web mapping applications on my own server?
yes you can do that, check this out: Web AppBuilder for ArcGIS (Developer Edition) | ArcGIS for Developers
and here is an example of a hosted webapp ArcGIS Web Application
For addition tips and links for customizing further, if you so desire, check out Web AppBuilder Developer Edition - Resource List (updated 5/13/2018)
there are many custom widgets being built beyond what you download from AGOL.
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