Q: iPhone 4S unable to turn off 3G?!

Ok, I get that, but worldwide, what has changed.  Are CDMA iPhones different to what we have here in that we can turn of 3G? Or would they all be the same from generation of iPhone to iPhone?

I mean obviously I isn't just me or Australians that have this issue, but everyone around the world......

CDMA is a different system from GSM. The only offiical iPhone providers with CDMA and using EVDO that I am aware of are Sprint and Verizon.

http://gizmodo.com/5637136/giz-explains-gsm-vs-cdma

The first CDMA iPhone was the iPhone 4.

The iPhone 4S is a "world" phone which means it has a combination GSM/CDMA chip.

So in other words, there is no way to segregate the bands?

It would all be a moot point if there was enough 3G coverage and bandwidth available on the AT&T network.

But I really don't understand why there was a control on the older phone models that is no longer there regardless of what Verizon and Sprint are doing.  If this control is also missing from the iPhone 4 w/iOS 5 then it's really strange.  It's still there on the iPhone 3GS w/iOS 5.

Are the AT&T iPhone 4S's now the same for all carriers?

Disabling 3G is the only way to make the iPhone usable in certain areas.

Did you read the whole thread?

The option is available with the iPhone 3G, 3GS, and iPhone 4 GSM.

The option is not available with the CDMA iPhone 4.

Once again - the iPhone 4S is a "world" phone which includes a combination GSM/CDMA chip and the CDMA iPhone 4 does not include the option.

Knot plus knot equals double knot.

And disabling 3G is not the only way to make an iPhone 4S activated with a GSM carrier usable. If 3G network access is not available, the 4S will switch to EDGE or GPRS autoamatically.

Sorry, no I have not yet read the whole thread.  There's an awful lot of information and misinformation to weed through.  I'll get there eventually. 

Obviously not or the option would be available with the 4S as is avaialble with the iPhone 3G, 3GS, and iPhone 4.

@Allan Sampson

I understand the "world" phone concept and that does make sense, but I would think that it's still technically possible to toggle on/off one or the other (CDMA/GSM). 

I also understand the part about the 4S switching to edge or GPRS automatically if no signal is available.  The problem is that in many cases the signal is great, but no bandwidth to do anything.  There are some areas where I can have full signal, but the phone cannot make or receive calls or transfer data.  This is where turning off 3G was most useful.

Apparently it is not possible with the combination GSM/CDMA chip or it would be available. This wasn't removed by some whim when it is available with the 3GS and iPhone 4 GSM running iOS 5.

I have not experienced the same as you are describing - not once.

Well, that's not much of an answer.  Just because a feature or control isn't there doesn't make it not technically possible. 

We experience that kind of thing often enough in Colorado (4 iPhones in our family - 4 generations), and I've experienced it in other places too, such as Atlanta and San Francisco.  Reading through this thread it appears that we aren't the only ones, and that those who have never experienced it somehow dismiss the notion.

Once again, the option is not avaiable with the CDMA iPhone 4.

The iPhone 4S has a combination GSM/CDMA chip.

If it were technically possible with the combination chip, the option would be available with the 4S as is avaiable with the 3GS and iPhone 4 GSM running iOS 5.

Ummmm, so the iPhone 4 is a CDMA phone????  I think I am getting a little bit confused about all of this now.....  :-S

There are two versions of the iPhone 4 - GSM and CDMA.

The iPhone 4S includes a combination GSM/CDMA chip.

There are not two versions for the iPhone 4S.

Someone who activates an iPhone 4S with Verizon or Sprint can request the GSM portion be unlocked so the iPhone can be used with a GSM carrier's SIM card when traveling outside of the country.