Help with PDA version application

I have an application that must be available for several navigators,
PC, PDA. At the moment only it has the version for PC.
Somebody could advise to me as it is the best form to treat this one
subject, in all the related one to controller, views and actions.
I must duplicate to controller and views and break with it DRY, or
only actions and views, or no of these things.
Somebody can put to me in good way, please?.

Thank you very much.

Best Regards.