Tap Tap Revenge the second-most downloaded free application of the year from their App Store, and the most downloaded free game. In April 2009, internet marketing research company comScore announced the results of a study which claimed 1 in 3 U.S. iPhone OS users had downloaded the game, and that it was the most popular application for the iPhone and iPod Touch. As part of the 2nd generation iPod touch advertising campaign, Apple featured "Tap Tap Revenge" in print and television ads with the headline "The funnest iPod ever.". The game spawned three direct sequels, "Tap Tap Revenge 2", "Tap Tap Revenge 3",
IPod Touch date has been introduced with the same release number of iOS as the contemporary iPhone model. Successive updates to iOS since the initial release in 2007 have released additional features. iPhone OS 2.0, released on July 11, 2008, introduced the App Store, which allowed third-party applications for the first time. iPhone OS 3.0, released on June 17, 2009, added features such as cut, copy, and paste, data tethering and push notification support. iOS 4.0, released on June 21, 2010, introduced iBooks, FaceTime, and multitasking. It dropped support for the first generation iPod Touch. In June 2011, iOS 5, the fifth