Really fun game! Worth it to take a look!
Chocobo tales is a collection of minigames hidden in books. That pretty much sums it up. The storyline was there, but you just had too much fun playing the minigames to care that much. For most all the books, there are 2 options: Time Trial and Battle.
You generally start off with only the option of Time Trial. In this mode, you're timed (GASP) and you try to complete a task within a certain amount of time. Whether it be Seeing how long you can outrun Leviathan, or riding an Adamantoise down rapids to save a cactaur from becoming Bismark's dinner, it's a race against time! Once you complete Time Trial (generally the easy times, such as it takes you about 50 seconds the first time, but to unlock battle mode you just need to complete time trial in under 2 minutes) You unlock battle mode.
Battle mode has 5 Levels, in Level 1 you face off against a relatively unintelligent chocobo (nicknamed a "jailbird") in the same event as time trial, only with a little twist. Take the racing of the Adamantoises down the rapids for instance. In time trial, you try to get to the end as fast as you can. In Battle, you try to get to the end before your opponent. in level 2, you face off against 3 Jailbirds. Level 3, you face off against the comic releif villains, a pink and blue chocobo. Level 4 you face off against the pink and blue, along with a mysterious black chocobo, who is not to be taken lightly. Level 5, its mano-a-mano with the black chocobo, which can be rather difficult.
Each book has a backstory as well. It starts off by telling the first part of the story, leaving you at a cliffhanger for you to finish. By completing the time trials in a certain amount of time, or by beating certain battle modes, you unlock a total of 3 Epilogues, which do crazy things to the world outside the book.
Another feature in Chocobo tales are the pop-up duels. Pop-up duels is where you face off against an opponent using pop-up cards, obtained in various ways (mostly by beating minigames and through the books). This is the game's wi-fi multiplayer feature. Pop-up dueling is surprisingly fun, but is limited to a deck of up to 15 cards, which I am sort of dissapointed about. All in all, it's a really fun game, and worth every penny to pick up.