Apps like 'Solve' as a Subroutine ???

[BERNARD MICHAUD]

Does anyone know if it is possible to access an App such as Solve as a subroutine and return to the calling program upon exiting the App.. Can a Solve App be made by a user and a RETURN button be inserted in the soft key area which is vacant between the = ..... Show keys. That would be so useful. Would HP put that in with a future upgrade? or is it already in place and I haven't discovered it yet?