Why Pokemon Ultra Sun and Ultra Moon are on 3DS

Announced in the Pokémon Direct today, Pokémon Ultra Sun and Ultra Moon are two new mainline entries into the storied Pokémon franchise. Taking place in the Alolan islands from the previous entries, Pokémon Sun and Moon, the new versions follow an alternate story on the islands. Each will feature new Pokémon and add existing Pokémon to the island for players to discover