That's because porny apps seldom make the best-selling list, which is dominated by games.
To succeed, they need to stay on the top 100 list for one of several porn-friendly categories, including "Lifestyle" and "Photography.
Ben Cousins, who makes adult apps as well as other apps targeted at 20-something males, says that once an app falls off those lists, "sales can be pretty dismal." Even holding a place on those lists doesn't necessarily prove lucrative.
It's Instagram's Valencia-filtered world and we just live in it—so why not play the game?
Curating a great Insta gallery can require some serious attention to detail, and there's nothing wrong with receiving a little assistance from some great photography and video apps.
Feeling bored with X-Pro II and Nashville filters on Instagram?
VSCO Cam offers more realistic photo treatments and enhancements, with an easy-to-use interface that makes cropping photos much easier than on Instagram itself.