How many people will buy your iPhone app today? Probably none.

Did you know that there are over 52,000 apps in the iTunes App Store? Over 14,000 publishers? Or that 1% of publishers are responsible for over 30% of apps? Did you know that the App Store is currently growing by more that 1,300 apps per week?

Fun with numbers!

I love digging into brand new data when the only strategy is to dive in and explore. The output of every query is a real discovery.

It's even better when its a huge pack of exclusive data about a cutting edge and very trendy topic. Today it's the iTunes App Store, which has been a subject of much study this year. Pinch Media published a presentation that gives some insight into how app ranking translates to daily downloads, and a recent report by MobClix examines the distribution of users among the 2,309 free apps they track. Both of these are based the subset of apps in their "network" and are not necessarily representative of the App Store as a whole.

I was lucky enough to get my hands on comprehensive, raw ranking data for the entire US App Store, spanning all the different categories. I have many days of it, but so far I've only begun to look at a single snapshot. Just for fun, here's a chart of paid vs free across all categories:


And here's another one with just games, by genre. Remember, games can appear in more than one genre:


Now that I've got you hooked with some colorful pictures, let's dig in deeper.

Clearly the majority of apps are not free. Yet if you browse any category in the App Store and sort by "Most Popular" you'll see that there are lots of free apps near the top. Below is a breakdown of paid vs free for the top 100 apps in each category.


Even though the majority of apps cost money, the majority of the "most popular" apps are free. To compensate for this, I'd expect there to be a concentration of paid apps at the bottom of the popularity curve. To test this theory, lets check out the 200 least popular apps in each category. (Games are omitted. Multiple genres makes it just a little tricky, and I'm keeping it simple for now)


This is starting to get exciting! Notice how most of the categories have no free apps at all in the bottom 200. It turns out that at the bottom of every category there are pages and pages of paid apps, uninterrupted by even a single free app. See for yourself - pick any category, sort by popularity, and click through the pages looking for free apps. It may take up to 50 pages depending on which category you chose, but you'll eventually find a page that has only paid apps. Keep on clicking and you'll see that this continues all the way to the last page.

We call this segment of paid-only apps in each category the "dead zone". App Store popularity is based on daily download rate, so the apps in the dead zone for each category have fewer daily downloads than even the least popular free app in that category.

So how many times per day are apps in the dead zone downloaded? Well, since the vast majority of downloads are for apps near the top, we assume that the least popular free apps in each category have very few downloads per day. Probably none.

Another interesting thing we noticed is that the size of the dead zone, and the percentage of paid apps that die varies quite a bit across categories. Here's another paid vs free chart with the dead zone carved out. I've also added a line showing the mortality rate based on total paid apps in each category. (You can click this chart to open a larger version)

If you're an iPhone App developer you may be wondering "What does this mean to me?", and you've probably got a hunch that it's not good news. Our interpretation is that most paid apps fail. These "dead" apps may have had some sales shortly after they were released, but once the honeymoon is over, that's it. No more sales.

I'd love to hear your feedback on this analysis, especially if you're the publisher of an app currently in the dead zone. Is it true that these apps are failures? Let us know!