diffrence between cdma and gsm iphone?

Stick to GSM, simple as that. Also, if you want to switch from Sprint to Verizon, you won't be able to and require new handset.

 

What is the difference between CDMA and GSM? Sadly, we'll never know, it's not like there's a limitless amount of information to be looked at online...

 

Since you don't have a location listed, I'm going to assume you're in the US. Here, Verizon and Sprint are the two major CDMA carriers. T-Mobile and AT&T are the main GSM carriers. The biggest difference (without getting into the technical side) is that GSM carriers use a SIM card (a small chip that contains your phone number and links with your phone account at T-Mo/AT&T) and CDMA carriers do not use one. The advantage of GSM is because the information is stored on the SIM card, if you buy a new phone then you can switch the SIM into the new phone and be good to go. With CDMA, you have to either log into your account or call Verizon/Sprint and have the service switched to the new phone. And since GSM is more widely used around the world, if you get your handset carrier unlocked, then rather than paying roaming fees when abroad, you can just pop a local SIM and be good to go.

Also, the link Interstella5555 posted has some more good info if you go with one of the first three links.

 

There are technical differences but that probably won't matter to you. Select the carrier based on coverage where you need it.

It's not that simple. At least provide the why behind this so others can assess whether your priorities are relevant to their own.

That's incorrect. LTE devices use SIM cards.

That's not unique to devices from GSM carriers. If you have a world phone from a CDMA carrier you can do the same thing. The Verizon 5 is already unlocked.

 

I didn't include those because they applied to pretty specific aspects. I was going for a more general explanation. But in hindsight I should've mentioned them because the iPhone 5 is an LTE device.

 

Does it really matter with these phones having GSM radio? Not like anyone keeps a phone for much more than 2 years anyway. Worst case you sell the phone. Not as big as a deal as it used to be.

In a nut shell its how it processes the call and/or data.