This project is there . Interestingly. It may be possible, but the most recent version of the Developer Agreement will actually prohibit the use of tools such as monotouch:
3.3.1 Applications must be originally written in Objective-C, C, C++, or JavaScript as executed by the iPhone OS WebKit engine, and only code written in C, C++, and Objective-C may compile and directly link against the Documented API.
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