Our app (shameless plug: itunes.apple.com/us/app/little-heroes/id477247738?ls=1&mt=8) cost $15K to make by a Toronto-based developer. We were able to keep the costs that low (I think that's a pretty good price for a better than average iPad app) because (1) all of the art was done in house and (2) all of the server side functionality was done in house. Our app developer just had to wire up the various pieces. (I say just sarcastically, it was still a lot of work).
If you have to outsource the entire cost of development, and you want a good looking, well functioning app, it's very expensive. And then there are the inevitable upgrades, improvements etc.
But what is the app worth? This sort of creative accounting is the problem that this article is trying to highlight.
If you strip out all the bullshit making an iOS app is going to be expensive because you can't cheat time and everyone's time is worth something.
If you mention to someone that you made your app "for only $15k" this just compounds the problem because that person has a skewed perception of what an app is actually worth.
If you have to outsource the entire cost of development, and you want a good looking, well functioning app, it's very expensive. And then there are the inevitable upgrades, improvements etc.