Is there a way that one can incorporate augmented reality marker code for augmented reality functionality within a GIS app?
Are you talking about the AuGeo app? https://marketplace.arcgis.com/listing.html?id=418dd96f17c342db8970457639563788
If yes, the AuGeo App that is currently available in the app store does not support "marker code" functionality. However, the source code of this app is available under Enterprise samples in AppStudio for ArcGIS Desktop, so it can be extended and customized to fit your needs.
Hope it helps,
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