If you go into your Options ,
then go into ‘Advanced’,
and then go into ‘Credits’

In there, among a lot of useless text about who built the game you’re playing (people schmeople), you’ll see a Skull. Click it a few times.
That’s right, that Skull ain’t dead. You just earned yourself the SelfPhone, which replaces your Options button that you just went through earlier.
You can now enter Genie codes like every other amazing Zombidler.

Leave a massage for the codes.