Demonstrating the cross-platform nature of the mobile gaming market, Glu Mobile has been releasing various tie-ins of Dreamworks' animated movie tie-in of Cressida Cowell's children's book How to Train Your Dragon, which hit cinemas last weekend.

Versions have been released for iPhone, Palm Pre and BlackBerry (pictured), not to mention Java and Brew. There's nothing on the Android Market though.

What's perhaps more significant is price differential between these games.

The iPhone version is $2.99, as is the Palm Pre version. The BlackBerry version is $6.99 however despite being the basic 2D version, not the 3D iPhone and Pre game. 

Of course, the Java version is being offered for free from various websites.

Further analysing the releases, it's notable that while the iPhone game is currently in the US top 20 of the US paid and top grossing US charts, neither the Pre or the BlackBerry versions have yet received a single review or star rating on their respective app stores.