Or half a millionth app if that sounds better to you. We've known for a while that Apple was the king of apps, at least in terms of most available, but this is an eye-opening milestone. For one thing, it far outpaces Android's 200,000. But a couple of other thoughts:
First, we're totally dinking around. The largest category of apps is games at 15%. Books are second at 14% and then there's the nebulous "entertainment" at 11%. A look at the charts shows Angry Birds at #1 (no surprise there), The Moron Test at #2, iFart Mobile is at 12. We're taking this amazing technology and using it to thrown cartoon birds, see if we're morons, and have digital fart augmentation.
Secondly, the app store is a librarian's nightmare. You have 500,000 apps but barely any way to discover them. The apps at the top of the charts tend to be the same small subset week after week, month after month. Some of them are great but there's no effective way to really browse and discover new apps. I'd be curious to see what percentage never get downloaded once.