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) history of the Apple App Store, "Angry Birds" holds the record for most days at the top of the Paid Apps chart, having spent a total of 275 days at the No.1 position; "Angry Birds Rio" has been No.1 for a total of 23 days, ranking ninth on the list. In Apple's "iTunes Rewind" list of the most popular iTunes Store media for 2011, "Angry Birds" was the top-selling paid iPhone/iPod app on the App Store and its free version was the fourth-most downloaded. The game's two special-edition versions, "Angry Birds Seasons" and "Angry Birds Rio", were also ranked in