How about just one unified portal that has all of the tech for all three built in (iOS, 3DS and ALL CONSOLES). That way I don't have like 8 of these around the house, oh yeah and won't have to pay almost $ 200 for all 3 versions. Maybe even have a little more foresight and incorporate some kind of plug and add tech at the bottom so when Skylanders 4 comes out, whatever new tech can just be an add not a whole new portal.
Real men play Skylanders, at least that's what my mom tells me.
There does not seem to be a good reason why it would not work for previous games. The reason for the new portal is that the old portal can't sustain the new figures that have two chip (swaps). We know the new portal will sustain all older figures.