An iPhone running on the next generation wireless standard, LTE, has long been a convenient technological avenue for dreams of the iPhone making its way to Verizon to come true. Even Verizon's CEO has said previously that the iPhone 4G is the most likely way it's coming to Verizon.
A quick tech primer: The current iPhone is a GSM device, so doesn't work with CDMA, the network technology used by Verizon. However, Verizon is using the GSM-aligned LTE as its 4G wireless technology, meaning it'll be using the same networking tech as AT&T and most of the rest of the world. (Check out our in-depth explainer on GSM vs. CDMA for more details.) So an LTE iPhone would technologically work on AT&T and Verizon, seamlessly, and run at superfast wireless speeds. One phone, both networks. That's the fantasy.
Let's talk about the reality.
LTE coverage is going to suck for a few years
It's genuinely impressive that Verizon's going to cover 38 major cities with 4G by the end of the year, along with a handful of airports. That's a little more than a third of Americans. AT&T isn't launching LTE in earnest until the middle of next year, and they hope to cover around 75 million people, a little less than Verizon. Thanks to the magic of competition, they'll probably be launching their 4G networks in roughly the same areas, covering the same people, provided they have the requisite spectrum. That's a pretty limited area.
Even if both networks managed to cover half of the country by 2011, that's not a lot when you're talking about about cell coverage—particularly if this iPhone only worked with LTE, and not Verizon's CDMA network. And rolling networks is a painful, bumpy process. Just look at WiMax, or even AT&T's 3G network. Even in cities with LTE coverage, service isn't going to be perfect or amazing to start. The spectrum both companies need to launch the new network is a limited resource, particularly in Verizon's case. So the ubiquitous next-gen network needed for a flawless LTE iPhone is going to take at least a couple of years after it launches initially. (Update: As a lot of people have noted, there's no voice standard for LTE yet, so it'd have to be a hybrid CDMA phone anyway to make phone calls.)
At a minimum, a Verizon iPhone would have to be LTE-CDMA for a couple of years. So a single model wouldn't work on both networks—why not launch a CDMA iPhone sooner?
Apple is a selective early adopter
Apple can be seriously aggressive when it comes to picking up new technology and dumping legacy standards, if it feels those standards are holding it back. It shitcanned floppy drives before anybody else, while it was among the first to jump on FireWire and USB. Key point: USB and FireWire were ready to go.
But the very first iPhone didn't use 3G. Partly because AT&T's network obviously wasn't ready for the onslaught of millions of devices using 3G speeds. (Could you imagine millions of iPhones running around, sucking down data at 12 megabits a second? Think even Verizon's network could handle that just a year from now?)
It was also partly because the iPhone wasn't ready. The battery life would've been even more abysmal sucking down data at those kinds of speeds. (Truth, one of the major iPhone 3G complaints was battery life.) Wanna know what the battery life would be like on an iPhone with LTE? Just look at any review of the HTC Evo, when it's running on WiMax. Crapola doesn't begin to describe it. The benefits don't outweigh the costs right now.
CDMA just makes sense
The simplest explanation for things is usually the right one. Which sounds more logical: An iPhone coming to Verizon banks on a bleeding edge network technology that's only available in select areas with spotty coverage and destroys battery life? Or an iPhone just like the regular GSM model that simply uses a CDMA chip?
It's more or less well known that Apple's kept a CDMA-compatible iPhone in development parallel to the current models, much like it kept an Intel-compatible OS X build on the backburner for most of its life. Do you really think one little chip is what's kept a Verizon iPhone from happening? The thing that's stood in the way isn't technology. It's politics.
Maybe the AT&T exclusivity agreement is finally up. Maybe Verizon's decided it wants the iPhone bad enough. It sold three million Droids. Imagine how many iPhones it could sell.