This sample demonstrates how you can set the spatial reference on a AGSMap. The operational layers will project accordingly.
How it works
The map in the sample app is initialized with esriSRProjCS_World_Bonne (WKID: 54024) spatial reference using (instancetype) - initWithSpatialReference: initializer. Hence the map image layer that is added, with default spatial reference as GCS_WGS_1984 (WKID: 4326), gets re-projected to map's spatial reference.