Complex sentence: It was the second game from the franchise to be released on Wii U, but is also available at the App Store and the Google Play store and will be free until Ubisoft decides how to earn revenue from the game.
Split into simpler sentences: It was the second game from the franchise to be released on Wii U, but is also available at the App Store and the Google Play store. It will be free until Ubisoft decides how to earn revenue from the game.