AGOL should allow update functionality of Hosted Feature Service Layers that were created with Excel sheets.
Currenlty, if you upload an Excel or CSV, geocode it, and turn it into a Hosted Feature Service Layer, you can update the sheet itself with the UPDATE button, but the Hosted Feature Service Layer does not change.
So, if you have a common workflow around a shared layer of store sites, etc, that are updated, you have to do it by hand in Hosted Layer, or make "yearly" or "version-ed" layers from continually uploading new Excel sheets.
This latter workflow means that all maps that you want to show the "stores" or whatever in have to be re-setup with the new data.
I know you can do "update" from desktop, but we are an all AGOL/BAO shop. Seems like a glaring missing piece, really. I thought it was demo'd at UC last year, but that must have been from desktop only. Meanwhile, this year, the big demo was for tiles made from a layer auto-sensing a change in the underlying layer and tripping an update of the tiles. So, clearly ESRI knows this workflow is common, and should wish to automate it.