Thanks Richard,
Yes. I can reproduce the issue. I also tested with the v10 released sample https://gitlab.com/thinkgeo/public/thinkgeo-mobile-maps/-/tree/support/v10/samples/iOS/GettingStarted
this one works fine after I changed the layer to bingmap layer. It use a different way to initialize the map. Anyway we will released the V12 xamarin form edition next week. So I recommend use the V12 xamarin form next week as Ben mentioned in the
RequestDrawing not redrawing layer
Thanks
Frank