Yeah, web's got a point. not many games start with 0 lives.
Knowing him, he'll make some pretty good levels. He's creative like that.
I like the vacuum idea. We'll need to add something that says to do that first though.
Web also had an idea to add the menu and a game over screen (with a retry button of course), for letting people test it. I imagine it's quite annoying to have to quit an app and run again every time you die.
How about save points, were you go back to if you run out of lives, and you can save. Like some sort of machine in game that saves your game and heals you when you walk over it. It'd only have to do this after a boss level, or after a really long set of levels. It should be challenging, but it's a little harsh to make a player start over the entire game after every death. I understand that's what the lives are for.
How about adding a survival mode, where zombies, ammo, armor, and bombs all spawn forever until you die. You would have one life only, and (If SC can do this, I don't know about it's online functions) try to get a high score online.
Also, maybe some difficulty levels. These would determine starting lives, zombie spawn rate, number of onscreen zombies at a time, and health.
Ok, that's it.
-zoo