This is one of these adventure games where you have to solve puzzles by finding hints and take actions to move the story along. It usually requires you to talk to the right people, find the right items, etc. as you are a part of the story.

Like this game: http://www.mobiletechreview.com/ubbthreads/showflat.php?Number=37564

or Hector: Badge of Carnage.

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MTR iPhone and iPad Game Reviews