I am looking for a similar page to this, an Experience Builder Custom Widgets. Does it exist? I am aware of the EB geonet page.
Nope one does not exist yet.
The more I watch about EB the more I get discouraged. EB was created to make easier to build mobile apps. However, it is not nearly as easy to create custom apps like WAB and provide the same functionalites. Yes, EB looks very visually pleasing and it has the wow factor. However, with WAB is lot easier to build custom widgets to perform search to view the results on the map and on a table. How hard is for the ESRI to modify the core files of the WAB to point to the JS API 4.x?
That making WAB 2D use the 3.x API would basically be a near complete rewrite. They will not invest in that. EB is the new product but it is in it's infancy just like WAB as years ago. Best advice is, be patient.
ExB is just 1 year old, and personally I'm pretty impressed how much you can do with it for such a young product.
It does have a learning curve but it's not that bad for a drag-and-drop experience.. Also, I wouldn't say it's meant to build mobile apps - you have AppStudio for that.
ExB allows you to better customize the layout of mobile and once you understand the "best practices", I was pretty surprised to see how good it works.
If you're referring to the coding aspect of it, then yes, it's definitely harder, but learning a new technology is rarely a easy/smooth thing to do.
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