Verify your Xamarin environment for All platforms

All platforms >> Android , Windows Phone , iOS

First, select Tools > Options, expand Xamarin > Other, and click the Check now link for updates. You need to be using Xamarin or later to avoid previous licensing issues.

Then create a new Xamarin solution in Visual Studio using File > New Project, then in the dialog expand Templates > Other Languages > Visual C# > Cross-Platform, select Blank App (Native Portable), and click OK. This creates a solution with a shared portable class library project and individual projects for Android, iOS, and Windows:

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