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Brightly-coloured trains and trees rub alongside the sinister black flag of the Islamic State on the cover of the terror textbook.
The download is available for Android phones and tablets only as ISIS bans Apple products over fears users can be traced by intelligence services.
It raises questions as to how Android could allow a terror app to be created.
The tech giant runs an "open source" scheme where developers harness the Android system to create products that can be used on compatible products.
ISIS is desperate to get the next generation of fighters ready to join its twisted religious war.
Commanders are so short of troops that they are plugging the gaping holes in the frontline with kids plucked from orphanages.
They’ve set up children’s homes in their captured towns and cities and are brain-washing vulnerable kids with violent jihadi films.
This picture shows an explosive vest used by suicide bombers.... ... and a grenade in the book aimed at very young children Boys dress in camouflage gear and begin military training when they are just seven years old so they can be turned into the next generation of fighters.
Disturbing pictures and video of an orphanage in Mosul, Iraq, show youngsters settling down in front of a TV to watch ISIS propaganda videos and boys dressed in combat fatigues performing military exercises in a playground.
ISIS is suffering from a chronic shortage of troops due to fewer radicals travelling to join the regime from foreign nations and punishing air strikes and land offensives.
A young boy shooting a prisoner in an ISIS video ISIS has an appalling record of using children in many of its gruesome propaganda videos, calling them 'Cubs of the Caliphate '.
Youngsters have carried out the execution of spies and captured enemy soldiers with guns, knives and even explosives.
And boys under 16 have been used as suicide bombers in Syria and Iraq.
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