Which mobile app has been launched by Islamic State (IS) for children to teach them Arabic?

Huroof
The terrorist group Islamic State (IS), also known as Daesh or ISIS or ISIL, has recently launched its first mobile app “Huroof” for children to teach them the Arabic alphabet and it has full of references to weapons and jihad. The app has games for memorizing and how to write the Arabic letters in addition to including a nasheed (a cappella Islamic songs) designed to help teach the alphabet. The lyrics in the nasheed are littered with jihadist terminology, while other games within the app also include militaristic vocabulary with basic words like tank, gun, rocket, etc.