在 Xamarin 的团队，从Novell工作的的单项目，已经开发出跨平台编译器和运行时间为的iOS 和的Andr​​oid 。

The Xamarin team, formerly employees from Novell working on the Mono project, have developed cross-platform compilers and runtimes for both iOS and Android.

虽然它尚未创建移动应用程序开发的写一次，到处运行的乌托邦，它肯定是在朝着正确的方向迈出的一步，比HTML5解决方案也许是更好的。

While it doesn't yet create a "write-once run anywhere" utopia of mobile application development, it's definitely a step in the right direction and perhaps better than HTML5 solutions.

我发现它***写核心库（仅仅是应用程序的逻辑，没有UI code），根据.NET和Mono编译。然后，写具体到要支持的每个平台的UI层。使用MVC模式，您可以用这样的方式，使code很可重复使用的抽象的东西。

I've found it best to write core libraries (just the app logic, no UI code) that compiles under .NET and Mono. Then, write UI layers specific to each platform you want to support. Using an MVC pattern, you can abstract things in such a way that makes code very re-usable.

MonoTouch的和MonoDroid工具包是免费的在模拟器使用（MonoTouch的仍然需要OS / X），但商业产品，并要求许可证与创建分发应用程序。

The MonoTouch and MonoDroid toolkits are free to use in an emulator (MonoTouch still requires OS/X), but are commercial products and require a license to create distributable applications with.