ISIS have created an app for children to help them learn Arabic via aids such as guns, tanks and cannons.

The smartphone app Huroof, which means alphabet or letters in Arabic, was promoted by the terror group's "Library of Zeal" propaganda department. It promises to "teach the cubs of the caliphate the letters of the alphabet".

The app is presented in bright colours with cartoons of balloons and flowers. However the child-like imagery disguises the militaristic themes throughout.

A tank is used for the Arabic letter "dal", a gun is used for "ba" and "ta" is illustrated with a bullet. Rockets, canons and swords are also used. Caleb Weiss, who first reported the app for the Long War Jounral, said the games and songs used as teaching aides were "littered with jihadist terminology".

The app was publicised with a press release with sreenshots of the app and links to download. It appeared on ISIS messaging on Tuesday and appears to be only available for download on Android devices.

The app is ISIS' first aimed at children but it has frequently used other apps to promote their messages and propoganda.

The softer appearance of this app marks a sharp contrast to ISIS's previous engagement with children in their propoganda. It has used young boys as suicide bombers and fighters and featured children as young as four in execution videos.

Refugees fleeing ISIS have described atempts to brainwash their children, who ISIS refer to as "cubs of the Caliphate". ISIS fighters are described as "lions". Parents have also described children being sent home with white dolls dressed in jumpsuits to be executed for homework.