Hello readers,

This is Bright Chong, writing the sequel for my first post, “GSM, CDMA, WCDMA? SO CONFUSING!“. In the previous article, I have explained the concepts of GSM, CDMA, and WCDMA. However, I have never elaborated the details  on the phone compatibility with these network infrastructures. Also, I have been noticing a lot of readers have been questioning.


– All phones that are compatible with GSM are also compatible with WCDMA. It is because GSM is the technical standard for 2G networks. In the 3G World, CDMA has evolved into WCDMA (World Wide Code Division Multiple Access) network which “smartly” uses sim cards. Therefore, any GSM phone will have a WCDMA antenna attached or it would be a 2G phone.


There are still some 3G CDMA (EV-DO) phones that do not use sim cards. However, most CDMA carriers have utilized WCDMA technology so you are able to use sim cards. These phones could be unlocked and used with GSM/WCDMA carriers such as T-Mobile. Although there are very little CDMA phones in use, if there are any, it is not compatible with GSM/WCDMA carriers as it cannot carry a sim card.

I hope this has helped to solve your questions. If you want to consult with me directly for selecting your phones… Please email me at