Just got this on my iPhone and it's pretty fun. I can say its a big improvement from the original one. Also has some awesome features like voice chat. The maps it comes with are Kino and Ascension and you are able to purchase others, but I'm happy with these two for now. The gameplay isn't may get laggy sometimes but it helps if you close apps running in the background. Overall if you I think it's worth the price and if you liked BO zombies you would love this mobile port.
Also if you want to play sometime add me on Game Center: Ninja_Fish1998
Also if you want to play sometime add me on Game Center: Ninja_Fish1998