Two months ago, when Microsoft acquired Xamarin, a lot of bold promises were made to make the development tools more open and available. Today there was follow up, with Microsoft open sourcing the Xamarin SDKs for Android, iOS, and Mac under the MIT license open source license and contributing the code to the .NET Foundation.

The announcement was made by Miguel de Icaza at Xamarin's Evolve developer conference in Orlando, and the organization also launched open.xamarin.com to provide easy access to all of the unit's open source components.

"The Xamarin engineering team will now be working in our repositories on GitHub, continuing to make the Xamarin SDKs better,"  wrote de Icaza, in a blog post accompanying the announcement. "We encourage you to interact with them on GitHub, file issues, make feature requests, propose improvements, submit pull requests and make the product better for everyone."