Apple has posted detailed breakdown of the differences between the CDMA and GSM iPhones in the HT4515:
iPhone supports many phone features, including call waiting, call forwarding, and conference calls. Depending on your wireless carrier's network technology (GSM or CDMA), there are different methods for enabling and using these features.
This article outlines how to use these features on your wireless carrier's network.
These phone features behave differently based on whether you are using a GSM or CDMA network:
- Call forwarding
- Call waiting
- Caller ID
- Conference calls
- Inserting pauses when dialing
When using an iPhone 4 (CDMA model), you may notice the following differences:
- Contacts or phone numbers on webpages that contain alphabetic characters beyond seven digits may not dial as expected. In these instances, either remove the additional letters or use a pause to dial the extension (555-1212,1234).
Example:1-800-MY-IPHONE or 555-1212x1234
- The following settings and features are not available on iPhone 4 (CDMA model):
- Enabling a SIM PIN
- Importing SIM contacts
- Selecting a carrier network or editing an APN