When on one hand, Google and Oracle are tied in a fierce battle over the use of Java in Android’s Dalvik code; a group of hobbyists has ported the Dalvik core to C#. The project is called XobotOS and it comes from the same guys who made Mono for Android.
XobotOS is a Xamarin research project that explored porting Android 4.0 from Java/Dalvik to C# to explore the performance and memory footprint benefits of C#.
The C# port is semi-automated. A major part of the codebase was created using a tool called Sharpen, that can port Java code to C# effectively. The rest of the port was created manually. You can visit the project’s GitHub page for more details. The C# port of Dalvik is released under the Apache 2 license, and the Sharpen tool is released under GPL.
Android being ported to C# is good news. It is good to see that people are hacking Android and creating their own versions of awesomeness. But wait, it gets better! On comparing the port to the actual Dalvik core, it was seen that the ported C# version had drastic performance improvements over the existing Java based Dalvik core.
XobotOS started out as a fun project and has achieved a marvelous feat. Sadly, the Xamarin team has a different focus going further. It has announced that XobotOS was an experiment, and it will not be developed any further. Nonetheless, this project has demonstrated clearly that when it comes to performance on mobile devices, C# beats Java hands down.