What&#x27;s interesting about Xamarin is that they are very local about OSS (Miguel) but what they did was not very &quot;open sourcey&quot; - obtaining a perpetual license for Mono and this way making sure that no one else can put Mono on Android &#x2F; iOS. Ever.<p>And then charging 1000$ annually per developer, per platform.<p>On the other hand they&#x27;ve made something that developers love (from what I&#x27;ve heard, I&#x27;ve never used Xamarin&#x27;s stuff personally) so they deserve the credits.<p>Congrats to the team.