John Gruber responds to my “Which iPhones survive the 12th?” post:

I wouldn’t count the 3GS out. I presume it will indeed lose its spot as the free-with-contract phone in the lineup, to be replaced by the iPhone 4, and the 4S will take over the $99-with-contract spot. But what about the low-cost prepaid market? If Apple wants to start taking market share in that market, my guess is they’d do with the 3GS.

That’s a lower-margin market than what Apple typically targets, but otherwise, they’re ceding it to Android. In the PC market, Apple ceded the low-cost segment to Windows, so perhaps they’re willing to do the same thing with phones. But I wouldn’t bet on it.

A good point about using the 3GS for prepaid phones and something I didn’t consider. 

Matthew Panzarino, writing for The Next Web back in July, adds that because Apple is making the 3GS iOS 6 compatible and the iPad mini will potentially use the same ppi display as the 3GS, Apple has an incentive to keep the 3GS alive.

So. Prepaid phones, iOS 6 compatibility, and the same display tech as the yet to be announced iPad mini. Makes sense.

The thing I keep coming back to is this: Is Apple really going to continue manufacturing four generations, (3GS, 4, 4S, and 5) of the iPhone? Assuming that the 3GS and the 4 are only produced in black, what does that lineup look like?

• (pre-paid) iPhone 3GS, black, 8GB, CDMA

• (free) iPhone 4, black, 8GB, CDMA
• (free) iPhone 4, black 8GB, GSM

• ($99) iPhone 4S, black, 16GB
• ($99) iPhone 4S, white, 16GB

• ($199) iPhone 5, black, 16GB
• ($199) iPhone 5, white, 16GB

• ($299) iPhone 5, black, 32GB
• ($299) iPhone 5, white, 32GB

• ($399) iPhone 5, black, 64GB
• ($399) iPhone 5, white, 64GB

That’s a lot of supply chain complexity to deal with. Could Apple juggle all of that? Absolutely. They have the best run ops team on the planet (other than Amazon) and their CEO is a genius at managing it.

Its more of a question of does Apple want to juggle all of that? Part of the reason their ops team is the best is that they make smart choices at the design, engineering, marketing, and operations levels to only focus on the essential and eliminate cruft.

That’s what makes me think that my hypothesis about killing the iPhone 4 might make some sense. Of those four generations, the 4 is the most…Complex isn’t the right word. Annoying? Let’s go with annoying…annoying to produce and manage if only because of the two antenna variants. If Apple could bring a lower cost iPhone 4S to their free tier, a model that they could send to any carrier regardless of signal, I have to think they would choose that option any day of the week over the iPhone 4.

After considering all of that, here’s where my baseless speculation ends up for the iPhone lineup on the 12th:

• (pre-paid) iPhone 3GS, black, 8GB, CDMA

• (free) iPhone 4S, black, 8GB

• ($99) iPhone 4S, black, 16GB
• ($99) iPhone 4S, white, 16GB

• ($199) iPhone 5, black, 16GB
• ($199) iPhone 5, white, 16GB

• ($299) iPhone 5, black, 32GB
• ($299) iPhone 5, white, 32GB

• ($399) iPhone 5, black, 64GB
• ($399) iPhone 5, white, 64GB

On a side note: Gruber rewrote my original post’s headline. The original was “Which iPhones survive the 12th?” and his edit is “Which iPhones Survive After September 12th?” I like his version better.