PRINCESS PETAL AND THE TRAPDOOR

A visually snazzy app about a bored princess is hamstrung by a weak story.

Princess Petal lives in an enormous castle with busy parents and "...one million toys / And one thousand games, / Dolls and pets, / And a small jet plane." But she's bored: She wants to explore the dark and dangerous place below the forbidden trapdoor. Of course, the scowling Princess Petal ends up below the castle, but what she finds there isn't particularly remarkable, scary or worth the trip. In addition to some squirming worms, a large monster readers never see and handy lights and electrical outlets, her chief discovery is a creature that looks like a mangy dog, which she befriends. It's all the more unsatisfying because the rest of the elements for a great app are in place. The sharp-edged art style, detailed and colorful, includes convincing backgrounds and witty design. And key words in the voluminous text are highlighted with specialized type. The word "ARMOUR," for instance, is in a steely typeface, while "ROAR!" is intensely ragged. Narration is animated and appropriately lilting for the story. But the ho-hum ending and lackluster middle ultimately make Princess Petal a lot less compelling than she should be.

Even with some nicely executed animation and an impressive look, the story of the princess and the trapdoor is too slight a narrative for its production work.