In the U.S., AT&T and T-Mobile are GSM carriers. Contrast with CDMA phone. See GSM. THIS DEFINITION IS FOR PERSONAL USE ONLY. All other reproduction requires permission.

One of the smallest GSM ... phone, GPRS high-speed data, EMS messaging, polyphonic ringtones, and tri-band world roaming. This phone is not currently available from any major U.S. carrier.

RCS brings a better messaging experience between iPhone and Android vs. SMS or MMS. RCS chats have some features found in ...