But here is where Apple drew the line: if you offer a free application, you can’t interrupt users asking them to upgrade to a paid version. (Or if you do, Apple won’t process the transaction through its new system.)
That is a slap in the face of developers who want to profit from the “freemium” business model that lures paying customers by offering a free version first. It no doubt is leaving a fair bit of money on the table. But implicit is an insight about how developers would likely use such a feature to make applications that are more annoying than useful.
That seems to violate the company’s apparent philosophy that customers should be willing to pay a premium price for things that are aesthetically pleasing.
Later in the article:
Apple, it seems, does believe in competition and capitalism, but only the decorous sort.