Apps for cats make sense in theory—they'll chase a laser pointer, so why not a digital critter racing around a touchscreen? But as anyone who's cycled through several brands of pet food will attest, cats are picky little cretins. Designing for them isn't as easy as slapping a mouse on a background and watching the profits roll in.

When the Atlantic consulted Martine Carlsen, creator of Catch the Mouse, she testified to the trickiness. This unusual market caught her eye when she downloaded several games for her own cats, a picky pair who found the offerings unimpressive. She set out to build a better version and found it easier said than done.

She learned, for instance, that the way the prey moves matters as much as how it looks—you've got to trigger Fluffy's murderous predatory instincts properly. Cats also need some reward when they catch their prey, like a satisfying squawk or squeak. (Not to mention cats can't hit the "buy" button themselves: "The design of the game has to appeal to humans to 'persuade' them to purchase it, and it has to appeal to the cat to be a success.") Long story short, you've got to learn a little something about cats if you want to appeal to them.

Even then, Carlsen discovered, you can't please 'em all:

"Cats are like humans in the sense that they have different preferences and taste in toys.... I try to make games with catch objects that appeal to as many cats as possible, but you can't please everybody (or every cat). It's like buying an expensive toy for your kid; they take out the toy and play with the box instead. You never know!"

Or you could just let them play Fruit Ninja.