Containment: The Zombie Puzzler is, in many ways, just a simple matching game, but they've really made some awesome additions and tweaks that have kept me far more interested than anything I've played in that genre.
Containment, from Bootsnake Games, is available for the PC through Steam and iOS.
Instead of a never-ending matching game, which I think is available on a "survival mode", there is a campaign mode where a short story about survivors banding together to fight off the undead horde. You get some special items to help in your quest to surround and kill the zombies. Some of these special items can also kill some of your survivors, but collateral losses don't seem to be too big of an issue.
The game runs $1.99 and I think it is worth it. I was a little confused playing it at first when I just started out because I didn't read the instructions and had to figure it out as I went along. To me that was even more fun because with the sound effects I felt a level of eagerness and anticipation that I wouldn't have had with any other game of this type.
Overall the graphics are superb and the sounds are great. This game had a bit more polish to it that what I'm used to seeing with cheap iPad games. Of course I will admit I don't purchase or play too many iPad games, but this definitely made the short list for me.