Interesting study looking at how frequently apps remain on the top download charts once they first crack the list. 74% of them drop out of the list within 30 days of their first appearance.
I think this highlights an interesting point regarding the App Store as a promotional tool. Obviously making these lists is far and away the most important factor in an apps chance of gaining national exposure. The thing is, isn't it in many ways a sign of general health of the ecosystem if apps aren't frequently able to stay at the top of the list for months at a time? I'm assuming this shows that while the low hanging fruit has been eaten up, there are certainly still opportunities for new entrants in the app developer model.
Running the App Store seems like a Herculean task. It's a multi-billion dollar platform with only a single entry point (two I guess if you want to count iOS and iTunes as two separate portals). As a customer, the experience of only having to deal with a one stop shop is absolutely delightful. As a developer, I can imagine that struggling to gain relevance in such a turbulent sea would be exasperating.
Apple experimented with a concept like "genius playlists" suggesting apps you might enjoy based on the ones you use the most and ones other users with similar interests tend to use as well. At the time, though, machine learning was mostly the stuff of research papers and hadn't started finding its way into consumer products and businesses workflows. Effectively it just said that people who liked Instapaper were likely to use Read It Later. It seems like today such a concept might be much more successful at surfacing useful information.