I've just released my latest app called '13 Monsters'. It's based on the concept of Blackjack yet the target is 13, and instead of suits there are the four elements. I'm happy with the concept, it means longer game-play, yet since the game gets progressively harder it's still a challenge. Just the fact that the target is 13 instead of 21 is enough to give your brain cells a wake up. It suitable for all ages.
I'm disappointed with apple in making me change the rating to signify 'intense gambling', as far as I'm concerned it's a card game yes, involves maths, yet no betting is simulated or required. Hmmm go figure??? Anyway enjoy.