I am looking at the possibility of using Survey123 for a UK customer. They would like to use their own basemaps (in British National Grid) and to capture locations in BNG Easting/Northing.
I have tried using alternate basemaps. The web authoring application allows selection of an alternate basemap - however it doesn't appear to be honoured by the iOS client app nor the Windows client app.
Are there plans to extend/improve BNG support and use of customer basemaps?