Author James Patterson took time out from his usual thriller novels to write a children’s picture book called SantaKid. Now it’s available as an app, courtesy of publisher Hachette.

Released in the US (but seemingly not elsewhere, yet) the app tells the story of a villain named Warrie Ransom who tries to rebrand Christmas for commercial purposes, before being stymied by Santa Claus’ daughter Chrissie.

Hachette worked with book-apps firm Auryn on the app, which adds animation, a virtual Christmas tree and a snowman-building mini-game to the book’s text and illustrations.

Patterson is joining an increasingly crowded market on Apple’s App Store for Christmas-themed children’s apps. Among his chart rivals this Christmas will be the festive digital issue of CBeebies Magazine; a game based on Channel 4′s The Snowman and the Snowdog; Celebri-gardener Alan Titchmarsh narrating a book-app called Angel’s Great Escape; and others still to be released.

Apple is expected to run several Christmas-themed promotions in its App Store over the coming fortnight, so there’s an opportunity for a few festive kid-apps to strike it big with parents over the holiday season.