BSP versus WebDympro

Hi guys, i would like to submit to all of you a basis question. I'm not a developer.

Suppose you have to develop some Mobile application (Online ) to be run on devices like PocketPC or Blackberry.

Wich should be the difference between BSP and WebDympro ? And in order of availability and supportability by next releses of Sap ?

And in terms of develop cost and time needed ?

The release involved are actually Sap 47 Enterprise Ext1 and Sap ECC5.

Regards