Zombie mode works if you keep the home button to the right (which is how I've always had it for sideways orientation). My thought is you need to boot up the game with the orientation this way for it to work properly. The game will auto calibrate in between rounds as well. I'm on 5s running 8.1.2 if that helps.
First you need to clear the level 13 to unlock the service module (located between level 13 and 14) Second you have 2 options 1- Touch the service module 2- Touch one zoorg with the cleaning indicator. The option 2 will give karma
Now you can play in your Apple Watch ! Subscribe to the TouchArcade YouTube channel Download: https://itunes.apple.com/app/id897407655?mt=8
Updated including the AppleTV new game with 3 games modes including versus and cooperative local multiplayer mode using your iOS device as a second controller. You can play some free games every day or pay only once the premium version ($2,99) and enjoy infinite games in your iPhone, iPad, AppleTV and Apple Watch.