Rovio on Tuesday released Angry Birds Rio for Android and iOS, though the game will initially only be available via the newly launched Amazon Android Appstore for those with Android devices.
"Amazon wanted to give it as a free gift to our fans in the U.S.," Rovio tweeted today.
Angry Birds Rio will eventually be available via other Android stores - like Getjar and the Android Market - but it will be "at least a week" until that happens, Rovio said.
Some customers were also complaining on Twitter about not being able to install the Amazon Android Appstore and Angry Birds Rio on AT&T phones. "AT&T working on that, should be sorted really soon," Rovio tweeted in response.
For a limited time, the full version of Angry Birds Rio is available for free in the Amazon Android Appstore, with no ads. The ad-supported version has always been free on Android platforms. In the App Store, Angry Birds Rio sells for $0.99, while an HD iPad option sells for $2.99.
The game has 60 levels, but more will be added in a future update.
Rovio announced that the Angry Birds Rio theme song is also available on iTunes for $0.99.
Rovio announced plans for Angry Birds Rio in January. It will be released as a tie-in with the 20th Century Fox movie "Rio", which follows a macaw named Blu, who leaves his native Minnesota for Rio when he meets Jewel, the bird of his dreams. It will be in theaters starting April 15.
On Monday, meanwhile, Intel said that it had teamed with Best Buy to give 50,000 people a free copy of the Intel AppUp center version of Angry Birds. Free copies of Angry Birds, which is usually $4.99, are awarded on a first-come-first-served basis for new customers that download and register for the Intel AppUp center. Users can sign up at the AppUp site. Intel has referred to AppUp as an app store in the past.