The film is shot in black and white, which mirrors the impression that we get in the book. The characters do not know what color is, and therefore cannot see it. Jonas, through the memories he receives from the Giver, is eventually able to see color, and this is shown in the movie as well.
There are several scenes in the movie that do not exist in the book. This includes the addition of a love story between Jonas and Fiona. While this was hinted at in the book, since Jonas recognizes feelings of love through his new memories, the movie dedicates much more time to their relationship.
There are a few new scenes added. For example, Jonas attempts to show Asher and Fiona was it is like to ride a sled by using a lunch tray to slide down an escalator-like ramp.
The ending is perhaps the most controversial new scene added. In the book, we don't know if Jonas does reach a town, or if it is just a piece of a memory that is comforting him. In the movie, there is less mystery about the ending, as we do see Jonas and Gabe reach a cabin. This makes the ending seem more final and happier.
The Ceremony is also different. Fiona is chosen as a Nurturer instead of a Caretaker in the House of the Old. Asher is chosen to be a pilot rather than a school teacher. These changes "up the stakes" as Asher is later ordered to find and destroy Jonas when he escapes the Community, and Fiona works closely with Gabe and Jonas's father.
The film uses narration throughout. We hear the voice of Jonas describing his feelings and actions. The film uses quite a few close shots to show the characters' emotions.