title: How to know the current OS / platform of the executing code (Android / iOS)
body: <p>Using Xamarin.Android and Xamarin.iOS, I need to now the current OS in a shared code section. Be it an enum, an int or a string, it doesn't matter.</p>
  
  <p>I tried this:</p>
  
  <pre><code>System.Environment.OSVersion
  </code></pre>
  
  <p>Which is always "Unix" with some kernel version informations.</p>
  
  <p>There are info on Android for example like</p>
  
  <pre><code>Android.OS.Build.VERSION
  </code></pre>
  
  <p>But it needs to be in the Android specific code section. 
  Is there any way of knowing the current OS in a common library?</p>