If the iOS app is running on a simulator or device configured with a proxy server (the usual case in BYOD), UriImageSource cannot download the image. The following example will not work:
var webImage = new Image { Source = "http://xamarin.com/content/images/pages/forms/example-app.png" };
It looks like XF's Image is using an HttpClient that is not aware of the iOS proxy settings.
Is it possible for the XF team to fix this? Or maybe, expose a way for us to specify our own HttpClientHandler? I have success using ModernHttpClient on Azure MobileServiceClient and YouTubeService.