400,000 iOS Applications Now Available In The App Store
appadvice.com
appadvice.com
This just proves to show that this number is not going to have any meaning anymore.
However the App Store has enough polished apps that work on all their devices that they can easily bury crap apps so they can only be found in narrow searches.
Android has a really hard time doing this because the best games don't work, or barely work, on older devices, or they are messed up on large screens, or they crash on some phone models, etc, etc.
So, on Android, the simple, addictive Indy games live at the top because the big games are sometimes providing a frustrating, rather than fun, gaming experience.