Angry Birds (video game) was being played, the staff liked the characters, and the team elected to design a game around them. In early 2009, physics games, such as "Crush the Castle", were popular flash-based web games, so the Rovio team was inspired by these games. During the development of "Angry Birds", the staff realized the birds needed an enemy. At the time, the "swine flu" epidemic was in the news, so the staff made the birds' enemies pigs. Angry Birds was the studio's 52nd produced game and on its initial release, the game did not sell many copies. After Angry Birds was a
Angry Birds (video game) of its spin-off games, "Angry Birds Seasons" and "Angry Birds Rio" to the PlayStation 3, Xbox 360 and Nintendo 3DS systems. Bundled together as "Angry Birds Trilogy", the games were built specifically for their respective consoles, taking advantage of their unique features, such as support for PlayStation Move, Kinect, high-definition displays and glasses-free 3D visuals. "Trilogy" was also ported to the Wii and Wii U almost a year later. A motion controlled version of the game has also been released as a Samsung Smart TV App. Reviews for "Angry Birds" have been mostly acclaimed by critics. Chris Holt of "Macworld"