The basic concept is an app (or other form) game where children learn a particular religion while playing a game.

I expect some poor attempts have been made, and specifically for one specific religion.

This concept can be expanded to include all religions, and allow the parents to configure which one or ones are allowed. Or all of course.

I have no concept in mind at the moment for a game, and expect adapting existing games with religious texts and figures would be difficult and confusing.