The latest example of the second kind is Eucalyptus, an e-book reader.
Eucalyptus downloads and formats books from the Project Gutenberg collection, which mainly consists of out-of-copyright titles but also includes some in-copyright items with the permission of the rightsholder.
And in accordance with the Project Gutenberg licence, Eucalyptus's developer pays 20 percent of the gross profits to the project, so let's not hear anything about charging for other people's work - the fee is for the software, not the content.
But back to the rejection-approval flip-flop.
What happened was that whichever Apple employee was given the job of vetting Eucalyptus, he or she noticed that one of the books available for download was the Kama Sutra of Vatsyayana - and promptly rejected it.
What happened next? Please read on.
This overlooked the fact that the application did not "contain" the material deemed objectionable, but could merely be used to display it. As developer James Montgomerie pointed out, the same content could be displayed using Apple's own Safari browser, the Google app, or other ebook readers such as Stanza.
Eucalypus is now available in the App Store for $US9.99/$A12.99.
But as far as App Store approvals and rejections on non-technical grounds are concerned, things need fixing.
Too many applications are being withdrawn after approval in the light of public outcries (think Baby Shaker or I Am Rich) or being approved after attention is drawn to their unwarranted rejection.
We're all only human, but you can see why some developers have been discouraged from working on the iPhone/iPod touch platform, despite the money some of their peers are raking in.
It's possible to spend several months working on a serious application, only to have it knocked back by Apple. And that would be a lot more painful than if you had only invested your spare time over a few weeks.