How to migrate the test scripts from Robotium to Appium

Hi All,

I know that Appium is great tool and I am using it currently. But I am trying to evaluate some options sothat I can ask my customers who are currently using Robotium to move onto Appium for their Mobile automation with minimal changes and efforts required. Hence I want to know if there is a parser to migrate Robotium based test scripts into Appium and similarly something for IOS also.
Please let me know if anyone has come across any utility / parser tool that can solve above problem.

Thanks,
Parveen