Full disclosure: I have not finished World War Z. I couldn't, on account of two problems: a) I reached what appeared to be an unresolvable bug, and b) if I'd played it any longer I would have gone on a rampage that would have made the need for burning city CGI in the upcoming movie redundant.
It is, by any standard method of measurement, one of the worst games I have ever played. Let's start with the fact that it controls like a drunk cow; there are many different control schemes, each as imprecise as the last. You can use virtual joysticks, or tap to move, which is so graceless it makes Resi's 'tank' controlled avatars look like Berbatov doing ballet. In one of them, you don't even fire the gun. In a shooter. Yes.
Then there's the basic game mechanics themselves, each seemingly part of some old-school Soviet experiment to break the minds of players. Broken down into exploration and fighting, the latter is so flawed and teeth-gnashingly frustrating you'd have more chance of survival in an actual zombie disaster.
You're armed with an ever-expanding arsenal of weapons, but for a lot of the time you'll be fighting zombies with, erm, a crowbar, or another melee weapon. You know those guns you have? Yeah, can't use those.
Instead, you've got to engage in some sort of insane dance-off, where a zombie runs at you, you dodge (maybe - input recognition is atrocious) and then bonk him on the head with your crowbar. You then do it all again like a drunk Gordon Freeman with two left feet. Alternatively, you can shove enemies back. Sometimes. It's up to the game really.
Gunplay is better; at times quite enjoyable and even a little tense. But then it all comes crashing down when you realise that this zombie game can't even get the basic rules right: shooting a zombie in the head should kill them, but here it can take 4-6 rounds to put them down. Even powered-up weapons don't seem to behave as they should.
It's artificial difficulty at its worst, attempting to cover for the fact the zombies seem to run in slow-motion, you can't move at all when you're in combat, and there's not enough of the undead. It also forces you to spend most of your time scavenging around the world for, erm, books, which give you extra XP on top of that awarded for killing the undead. Correction: you can also tap PC keyboards. Not interact with them, just tap them and you're done.
You can buy upgrades with the XP you've gained, and you'll need to do this regularly to keep the horde at bay. Of course, if you're not into the whole 'searching through every drawer like dawn-raid police officers on amphetamines' thing, you can, dun dun dun, go the route of in-app purchases, which give you gold and XP to spend. The most powerful weapons are locked away behind these, and although you can secure some gold in-game (and in the barely-any-better challenge/score attack mode) it's clearly designed to make you put your hand in your pocket again. Health packs also fall under this model, and in a game where getting hit is more a case of bad design than anything you've done, making players fork out for more of fighting chance is shameful.
As is the whole thing. Buggier than the virulant masses that besiege you, frustrating and, story-wise, uninspiring, this isn't worth anyone's time or money.
Version Tested: iPad
Played for 2 hours, before the game mercifully put me out of my misery.