"Big adventure with new birds coming soon! #NewAngryBirds," Rovio tweeted.The official website of the company states that the game will be launched in "in the fall of this year."

Rovio has in recent years expanded the Angry Birds brand into an animated TV series and merchandising of toys and clothing. Rovio has partnered with Bata to sell Angry Birds branded footwear for kids in India. 

Unlike most mobile-game crazes, Angry Birds, in which players use a slingshot to attack pigs who steal the birds' eggs, has stayed at the top of the charts since it was launched.