To me, it's not about how many devices they have and whether that makes sense, it's about the fact that they had spent $200,000, which then generated $5,000 (this year only, don't know how long they've been at it), they had to move to a smaller flat, the guy had to get another job, and then they just had to buy two new iPhone 5s (which are mentioned later on in the article). Why? Can you justify spending that if your income from iOS development is $5,000 a year? That what gives me the feeling it's an addiction.
Now, I assume the new iPhone 5 is so different to the ones before it (screen size) that you have to test for it separately. If I was down $195,000 in a year (or two) and I felt this, I'd buy a new generation iPod touch instead. Or two, if they really can't share the device.
I also look at the picture and I question if they really need 5 computers between them if they only work on the two laptops.
Anyway, my point is not that having X amount of devices (Apple or others) per person is an addiction, if you can afford it, go for it and enjoy yourself. My point is that this couple seem to be struggling financially and cannot stop themselves from buying more devices. I'm trying not to be judgemental, but to me it sounds like an addiction.
The article says it cost $200,000 "in lost income". That's not quite the same as spending $200K, they're factoring in opportunity cost to make it sound more dramatic. It's also possible that some of the equipment (eg laptops & displays) was purchased before they started iPhone work.
Definitely agree about iPod touches & cutting costs, though.
The 5th gen iPod Touch is not the same as the iPhone 5 - it is more like the iPhone 4S, as far as I can tell, but obviously with the larger screen.
Buying two certainly sounds like an extravagance. A better distribution of devices would be 1 x iPhone 5, 1 x 5th gen iPod Touch, 1 x 4th gen iPod Touch, which would cost about the same as 2 iPhone 5s and also give you a reasonable idea of performance on iPhone 4S (roughly equivalent to 5th gen iPod Touch) and iPhone 4 (equivalent to 4th gen iPod Touch).
That assumes your program is OpenGL- or CPU-heavy. If not, you can probably do fine with whatever you've got, plus the simulator :)
After you take out 2 phones you would have anyway, 2 laptops and maybe an iPad and an Apple TV there isn't that much more.