From the Store description:
Choose your skin, nickname and play extreme multiplayer modes with chat!
Choose your gun and enter the battle!
- up to 10 players online;
- a lot of cool maps ;
- awesome guns, from Laser Rifles to Heavy Axes!
RED or BLUE? Which team will won the match?
This cool mode allows you to fight team on team!
- You can set a password for a private game!
Try to survive with players online from all parts of the world!
- Many types of deadly enemies;
- Custom matches with awards;
- Easy and fast connection.
*** SINGLEPLAYER CAMPAIGN ***
In this mode your character is “face to face” with hordes of zombies attacking you from all sides. You have to wipe them out otherwise you are doomed!
Your only task is not an easy one - to whack all the monsters. If you survive all the attacks of the dead, you'll face an EVIL ZOMBIE BOSS. Having made mincemeat of him, you open the portal to the next battlefields!
And moreover you can play CRAZY ARENA MODE! How many waves can you stand!
How far you progress in Pixel Gun 3D will depend very much on how coordinated you are. With left thumb for movement and right thumb for rotation, reloading, firing and jumping, there's... a lot going on. Add in the usual FPS (First Person Shooter) elements of remembering where you are, where you've come from, where the zombies are around you, and so on, and I pronounce Pixel Gun 3D tricky to say the least. If you're up for a FPS that has legs, with tens of hours of gameplay then this is for you on Windows Phone.
Here's Pixel Gun 3D in action:
The $100 freemium purchase is, as usual, taking liberties and hoping for the slip of someone's finger - why can't we have a cap on IAPs? Something sensible, such as $10 for games? But I've ranted on all this before in the past...