That rules out Ace Attorney, Touch Detective, ...there are many Tamgotchi games for the DS, right? and Harvest Moon had multiple I think also. (is harvest moon an RPG?) Several Castlevania DS games, Cooking Mama disqualified...
Not for Khush Hey! What about Meteos? does that meet all the criteria?
edit: Nevermind, there was Disney style Meteos sequel on the DS. Ghost Trick is also on iOS so that is out too. edit2 Mister Driller came out in 2004.