title: How does one upgrade to Android SDK 25.1.3?
body: <p>After the latest update to Xamarin, I get this error in design view</p>
  
  <p>"The installed Android SDK is too old. Version 25.1.3 or newer is required."</p>
  
  <p>Running the "Open Android SDK" and installing the latest version of Android Studio did not resolve the issue.</p>