Apple has just cleared the half-billion mark* for iPhone, iPad and iPod Touch apps available in the app store. Whoa, whoa, whoa—asterisk?!

That’s half a billion apps that Apple has approved since the App Store launched back in July of 2008, though, as Fortune points out, “Through attrition, replacement and withdrawal, [the] number of apps currently available for download is 20% lower, around 400,000.”

And the inevitable question arises: How many of those are fart apps? I took the liberty of painstakingly counting the number of apps returned when searching for “fart” on an iPod Touch, and the result is 1,123. That’s not including iPhone- and iPad-specific fart apps either, mind you.

Therein lies the rub (for any app store). How many of its total number of available apps are actually good apps. That’s subjective, of course. You may love Tub Tooter or iSantaFarted—one replicates what farts sound like in a bathtub; the other is, well, pretty straightforward.

Numbers are not subjective, therefore companies that run app stores use numbers to attempt to portray the subjective goodness of their app stores. And it may be true that out of 500,000 apps, there are bound to be some winners in there.

Google’s Android Market, by comparison, reportedly contains upwards of 300,000 apps. It’s lagging behind Apple in fart apps, though, with fewer than 350 available, according to search results.

On a non-flatulent note, there’s a big infographic over at Facebook.com/500kapps that breaks down the Apple numbers quite nicely.

Some of the more interesting factoids:

– There are over 85,000 unique Apple mobile developers

– 37% of Apple mobile apps are free

– The average price for paid apps is $3.64

– Angry Birds is the most popular application of all time

– If you were to buy every currently-live, for-pay app, you’d spend almost $900,000

More on TIME.com:

Apple to Amazon: ‘App Store’ Isn’t Generic, and You’re No App Store

Now the Army Wants an App Store

Amazon’s Latest Weapon Against Apple in ‘App Store’ Lawsuit? Steve Jobs