Here at Sensor Tower, we've got a lot of data about the iOS App Store -- we can tell you the keywords of your competitors, track your rankings on a per-search basis, suggest relevant keywords and do a whole bunch more to make sure your app is as visible in the iOS store as possible.
However, we are always thinking of ways to visualize the whole ecosystem, to get a far away and bird's eye view of all the data. An overarching view like that helps visualize trends and see patterns in the whole ecosystem that might not be obvious otherwise.
The visualization is built using a technique called Parallel Coordinates, and the Reviews and Downloads axis are plotted logarithmically to help visualize things better. You can click on any axis to start filtering the output to those apps that only fall within the specified range.
There are about 37k apps that we've included: every app over 10 reviews that we have data on and that is an english-language app. The downloads estimate, reviews, ratings and price are all for the US App Store.
You can ask questions such as "what is the correlation between number of reviews and total downloads?", and simply by sliding up and down the axis figure the answers out (on average across all apps, developers get roughly one review per 62 downloads). Your numbers might vary a bit, as they depend on if you're using something like Appirater to ask for reviews, but that is the ratio to look for.
How about the correlation between number of keywords and number of downloads? This one isn't as obvious as the reviews-downloads relationship, but the more you think about it, the more it makes sense: Apps with more keywords will on average show up for more searches and get more downloads.
What do the numbers say?
Apps that have under 5 keywords get on average a total of 53k downloads. Apps that have between 15 and 20 keywords get 143k downloads, almost 3x the amount of apps that have under 5 keywords. And what if you don't input any keywords at all? Apps with only an app title and no keywords get 10.7k downloads on average.
The download data estimates might be a bit off -- they aren't always accurate, especially for apps that have been released recently. However, in aggregate when looking at many apps together the download estimates should be accurate.
Without a doubt, the Games category dominates -- both in amount of apps overall, and in terms of presence in the higher strata with regards to Downloads and Reviews.
A very useful feature is the ability to slide up and down the selection and see how the limits on one axis affect the other ones -- the green line is the average of all apps shown, and you can see it move as you place restrictions and change them. You can also filter by category, search for individual apps and even change the color scheme to an inverted dark theme.
So go ahead and check out Visualizing the iOS App Store and delve into the wealth of data we've collected for you.