Angry Birds (video game) featured app on the UK App Store in February 2010 and quickly reached No.1 there, it reached the No. 1 spot on the paid apps chart in the US App Store in the middle of 2010 and then stayed there for 275 days. The initial cost to develop "Angry Birds" was estimated to exceed €100,000, not including costs for the subsequent updates. For the iOS version, Rovio partnered with distributor Chillingo to publish the game to the App Store. Chillingo claimed to have participated in final game polishing, such as adding visible trajectory lines, pinch to zoom, pigs' grunts, birds'
Angry Birds (video game) were released, Angry Birds became "Free App of the Week" on the Apple App Store until March 14, 2013, and became an instant hit on the Top Free App charts on the App Store until March 18, 2013, when the app returned to the normal price of $0.99. On June 17, 2013, Rovio teased on its Facebook page that Red, the main protagonist of the game, would receive an ability in a new episode. On June 26, 2013, Rovio released a YouTube video, uncovering three new facts: the episode would be called Red's Mighty Feathers, the update would come in