As Apple kicks off international release of the iPad (which includes Canada, finally), rivals are working to develop their own products to claim a slice of a growing consumer market.

The new iPhone OS extends the set of APIs to over 1500. The iPhone SDK 4 provides developers with a broad range of technologies to enhance the functionality of their iPhone and iPod touch applications. Developers can use these new APIs to make their apps more powerful, more feature rich, and more amazing than before. They can even use new GameKit APIs to develop for Game Center, the social gaming network Apple will launch later this year.