None of the above the answer is a creative, yet simple game that can be played easily by everyone, and also being 0.99 helps lots.
What about line-drawing games? That should go up with the others I think. No one genre rules the entire store though.
Zombie games(is that a genre)? Seriously there is a huge majority of games that has a lot to do with killing zombies
There's tons of match 3 games available. Edit:I see you had added this genre already at the very bottom of the op.
Ninja games involving an assortments of fruit, Jumping games developed by a companies whose names start with L and ends with Y (with an "ima sk" in between), games where you hurls birds at bricks to try and kills pigs, and games where you are a God trying to kill innocent little pygmies.
Can't pick a genre but here's a list of good games : Ragdoll Blaster (1 & 2) Angry Birds Minigore Canabalt Minigore Doodle Jump Bird Strike Doodle Bomb Fruit Ninja Tilt to Live Finger Physics Harbor Master Flight Control Geared Ninjatown: Trees of Doom Project 72 Plants VS Zombies Tetris Doodle Army Guerrilla Bob Pirate's Treasure Zombieville USA
Doodle games. Doodle Jump. Doodle Bomb. Doodle whatever. I'm personally tired and sad that some devs can't come up with something different, but gotta admit Doodle games are flooding the store.
I personapy like 2d platformers like Spider:Seceret of Bryce Manner and Rolando. But I also like my physics games like peggle, angry birds, and orbital. Finaly there is Tilt to Live but I dont consider that to be a casual game.
Are you kidding? Games like More Salad are the very essence of what makes us human. Without them we are nothing. They are not simply "games," they are an entirely different entity that is closer to humanity than even humans themselves could ever possibly hope to be. Anyways, the OP forgot a genre that isn't really succeeding in the App Store market, but might as well be there: free-running games (i.e. Canabalt, Robot Unicorn Attack, etc.) Also, I don't think any 1 genre is ruling the App Store market; I think that whatever apps are the most well known that are ruling the App Store market.
There Are quite a few god simulations too: Pocket God Pocket Devil Forest Folk Bad Pocket Santa God-Finger
I think it's less about genre and more about what's fun and unique for me cogs, labyrinth and geared come to mind .. but i'm really into puzzles edit: the more i think about it games that take a concept and expand on it in as many different ways as possible seem to be what rule.. theres a huge pile of not quite there in the appstore