A few days ago I became the first app store developer to reveal sales-to-rank data.
Some other sites have confirmed an interest in this data, such as The UnOfficial Apple Weblog.
With iFart continuing its move up the charts, I want to continue sharing data with you, especially since something very interesting has happened since we broke into the top ten apps in the world.
Here is updated data from the time the app went live on December 12th, 2008.
The format is date, daily units sold, overall ranking (starting 12/14) and entertainment category ranking.
12/12 - 75 units - #70 entertainment
12/13 - 296 units - #16 entertainment
12/14 - 841 units - #76 overall, #8 entertainment
12/15 - 1510 units - #39 overall, #5 entertainment
12/16 - 1797 units - #22 overall, #3 entertainment
12/17 - 2836 units - #15 overall, #3 entertainment
12/18 - 3086 units - #10 overall, #3 entertainment
12/19 - 3117 units - #9 overall, #2 entertainment
12/20 - 5497 units, - #4 overall, #2 entertainment
So why the massive leap on 12/20? I can only suppose that either there is an exponential jump once you hit the top five, or the release of Sim City has been a rising tide that lifts all boats. SInce it rocketed directly to the #1 spot, there are many eyeballs looking at the top ten.
Either way, it's good for the entire app store and I think we've still got movement to go as we have our aims set on the #1 slot.

December 21, 2008 03:59 PM
Hi Joel,
Out of interest are you doing any marketing at all? or is the growth in those figures a function of the position the day before alone?
Also - your app doesn't seem to appear in the charts here in Australia, where pull my finger is at #4 overall... why do you think that might be?
December 21, 2008 04:03 PM
Hi Joel - great article. Your jump in sales once you reached #5 would probably be due to fact that iPhone shows only top 5 apps on first view. I think there is a similar jump once you reach #10, as this is how many iTunes show on first view. I have published my own rankings/sales comparison in the Australian app store here: http://ajnaware.wordpress.com/2008/12/21/how-to-estimate-app-sales/
I find a logarithmic curve rather than linear, although it probably looks almost linear across much of the range - apart from the very top end where it curves up sharply.
PS - Captcha on this site is very broken! Took 3 attempts.
December 21, 2008 11:16 PM
@Jonau:
Each international App Store has its own application inventory and top lists. Therefore it's not surprising that you see different apps on the Top 25 in Australia.
@Joel:
If you're counting total sales for all countries, but only tracking the ranking in the U.S., that could explain the big jump on 12/20 if the app made it to the Top 25 in another major market.
December 22, 2008 12:11 AM
Hi Nick,
Yes, I realize that... my point was that if the ifart app sales were growing simply on merit without any external forces (such as local marketing specific to the USA for eg) then its sales *position* should really correlate in each region. ie it is not even on the top 50 in AU I don't think which seems to be an anomaly?
December 22, 2008 10:44 AM
Any chance you can do the numbers just for the US, I think that's more interesting then numbers for all the countries (since the ranking is diff in all of them)
December 23, 2008 06:18 PM
Actually, I revealed a ton of sales-to-rank data back in early September. http://larsbergstrom.wordpress.com/2008/09/05/us-appstore-sales-and-rank-data-for-wifinder/
Still, thanks for releasing your numbers - they were interesting!
December 23, 2008 11:45 PM
dude! congrats.... it's a hit!
December 24, 2008 07:52 AM
Congrats, I wonder what you will think of next... :)
December 25, 2008 02:10 AM
how funny, the whole apple iphone app store is a big kindergarten.
December 25, 2008 04:52 AM
Joel
that is to funny. i was just telling my sister who had a farter near her on her Xmass plane ride from hell to nyc that she needed a fart cushion to fight back. now she does and its even better.She has a menu to choose from.
Congratulations! Curious to know what your cost was to build the app and on going support vs. revenues.
December 26, 2008 01:45 PM
WOW! These are great numbers to see! Don't think I will be downloading the fart application for my iphone but it's a great example of creating something that would have obvious market demand! Could be the best gag gift for 2009! Great work! And thank you for being so transparent with the numbers!
January 8, 2009 04:32 AM
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