This game should not be confused with the similarly named Dead or Alive Paradise for PSP, released over 3 years later which also was based on Xtreme 2 but featured more options, though none of the social aspect the mobile game provided.
DOAパラダイス♪ (DOA Paradise♪ ) was a mobile game released in late 2006 only for japanese mobile phones. The game is a very limited conversion of Dead or Alive Xtreme 2, only featuring a casino minigame and a way to interact with the girls available on it, which were only Kasumi, Ayane, Leifang and Hitomi at launch, with other characters like Tina, Christie or Kokoro being added in later updates. The game also showed a popularity contest among the playerbase on a regular basis which involved rewards for the players. There is very little information about this game and almost no gameplay recorded, if any at all, and because of compatibility issues with old phones it can't be purchased or played currently.