The creators of the film had no prior knowledge of how to make a movie, so it was based on their knowledge of in-game movies.
The opening scene of the movie is the closing scene of the original video game.
The phone used by Cloud is a Panasonic P900iV only sold in Japan. It comes in three colors, and the black one is called "Cloud Black" after the character's name.
In 'Advent Children Complete', there is a scene where Sephiroth impales Cloud on his katana; a reference to the famous scene in the game.
Tifa's fighting style against Loz mirrors some of her Limit Breaks from the game. She opens up with Beat Rush, comes back with a Water Kick, backs him into the corner with Somersault, and ends with Meteor Strike.