 The Mighty Eagle is offered as a one-time, in-game purchase, and was initially only available for iOS, as its App Store customers have iTunes accounts with pre-linked credit cards. In late 2011, Rovio also added the Mighty Eagle to the Chrome App version of the game. Rovio has begun testing an Android update called the "Bad Piggy Bank" with the Elisa wireless service in Finland and T-Mobile, which allows users to charge in-app purchases, such as the Mighty Eagle, to their mobile phone bills. The service went live on Android with the release of version 2.2.0 in August 2012, using Google Play's transaction system, which allows both mobile billing and credit cards, allowing both Android phones and WiFi-only tablets to unlock the features. This version also added the powerups from the Facebook version and added an option to pay to remove ads, allowing Android players to enjoy the game ad-free as iOS players do.
