Hi,
I am eager to know the difference between *.geodatabase file and *.ovl file(but I cann't found any url/link related to this topic). Please provide me the same in detail.
Where did you see the .ovl file from?
I believe that the .geodatabase is for the Esri Runtime product; Supported geodatabase formats—ArcGIS Runtime SDK for .NET | ArcGIS for Developers
