A senior Apple executive has refused to apologize for problems with the approval process for applications with the iPhone app store. That’s despite a combination of developers complaining that perfectly good apps get delayed or rejected, and some clearly inappropriate apps make the cut.

To recap some notable decisions, Apple has said “yes” to a game in which you shake your iPhone to put a crying baby to sleep, a fake branded watch display and a $999 screensaver, but “no” to an official Nine Inch Nails audio collection, an e-reader (because it might be used to access the Kama Sutra) and a rude sounds tool which promised the audio of “wet farts” (though it was then approved once this was changed to “big toots”.)

In an interview with Business Week, Apple’s senior vice-president for worldwide product marketing Phil Schiller (pictured) says around 10,000 apps are submitted each week. He doesn’t reveal what proportion of these get approved, though with “only” 100,000 apps getting the thumbs up so far, it’s clearly a big chunk. Of those which get rejected, Schiller says:

• 90% are rejected because they don’t meet the technical requirement and thus aren’t reliable enough;
• 10% are rejected over content issues; and
• 1% are rejected for previously unforeseen reasons such as gambling-related apps which specifically aid the user in illegally cheating.

(Having trouble adding up percentages? There’s an app for that.)

Schiller notes that the firm has now added parental controls over apps as well as tightening up its rules over applications which could breach trademark restrictions.

The big problem with what he says is that the interview seems to be mainly about defending the principle of pre-vetting apps. But I’ve not come across anyone who’s put forward a serious argument that the app store should be an unvetted free-for-all. Instead developers seem to be more upset by a perceived lack of consistency over content issues, along with a lack of information about how approval decisions are made and how quickly they can expect to hear back from Apple with a yay or nay.

To some extent Apple can afford to play by its own rules as the iPhone is still by some distance the most desirable market for app developers to reach. But with Android handsets now making up 20% of the US smartphone market (and rising), and virtually every operating system now having its own app store, it might not be long before developers find it is feasible to make a living without putting too big a priority on getting through the Apple process.