hey.. just a little q - how is the rank in the top paid apps list set? does it depend on the number of downloads in a day or the number purchased -as there's a difference between purchasing a new app to upgrading a ver (ex.pocket god episodes..) cheers
It's generally accepted that the top 100 ranks are a calculated 3 day sliding window of the number of units sold. Upgrades are not counted in that total.
hey thanks for the quick reply! but sometimes i've noticed the rank changes during the days... isn't it an online number of total downloads in a day? that's being updated X times a day? hmmm...
It is definitely a sliding window, rather than three full days just stepping forward once per day think of it more like 72 hours, and it bumps forward every couple of hours (not sure of the exact frequency, but probably somewhere between 2 and 4). So if a game had some odd sales spike in the first 3 hours of that 72 hour window, if you check it's rank again, those hours will have slid off the back end and it's rank would drop some. How much depends on what the new 3 hours brought in, and how much other apps immediately around the one you're looking at have changed in that same window. I'm sure there's plenty of seasoned devs here that would concur with this, if they weren't all busy making games Speaking of which, maybe I should go back to lurking and get some work done...
I can support the above; our data seems to support the 72-hour "sliding window" ("box filter" for you signal processing guys) theory as well. As far as I know, Apple has neither confirmed nor denied this, but observing sales 'spikes' it seems to be the case.
