title: How to perform Authentication and Authorization in Xamarin.Forms ?
body: <p>My authentication and authorization knowledge are based on web background where all I had to was to use <strong>"Authorize" attribute</strong> <strong>(ASP.NET)</strong> attribute , or maybe creating a <strong>"middleware"</strong> and assign it to a controller <strong>(Laravel)</strong>. </p>
  
  <p>What is the best practice of Authentication and Authorization in Xamarin.Forms using MVVM approach (with example) ? </p>
  
  <p>Do Android and IOS share the same implementation or there will be platform tweaks ?</p>