Ultimate Dinopedia: Complete Dinosaur Reference (for iPad)

The Ultimate Dinopedia iPad app would not have been complete without Tyrannosaurus Rex. Although not the largest carnivorous dinosaur, it was doubtless one of the most fearsome.

A Troodon chasing a tiny mammal, perhaps one of our distant ancestors. If your child is prone to nightmares, this might not be the best app for him or her.

The Ultimate Dinopedia includes some video animations of dinosaurs in motion, such as this one of Spinosaurus.

In addition to the entries on individual dinosaurs, the Ultimate Dinopedia has a "Discovering Dinosaurs" section that provides more general information.

Baryonyx, one of the few known species of fish-eating dinosaurs.

A dinosaur family tree, showing the split into their two main divisions (orders): ornithischian (bird-hipped) and saurischian (lizard-hipped) dinosaurs. The ornithischian branch went extinct at the end of the Cretaceous Period. Birds, which ironically belong to the saurischian group, are the only descendents of that group to have survived.

The Dino A to Z section is an alphabetical list of the critters in the app, but doesn't provide any information not given in the individual entries.

The world was quite different in the age of the dinosaurs. This map shows the Triassic Period, 250-200 million years ago, when the Earth was a single warm and wet supercontinent named Pangaea.

At the end of the app is a glossary of terms. Although the app is geared to 7-to-10-year-old kids, it's not afraid to introduce some advanced concepts where appropriate.

A page in the app is devoted to the mass extinction event 65 million years ago that spelled the demise of the dinosaurs. It is generally believed that the extinctions were precipitated by a comet or asteroid collision, but the app lists that as just one of several possible causes, others including volcanic activity and slow climate change, while stating that it could have been a combination of several events.