CDMA stands for Code Division Multiple Access and is a major technological channel access method used in wireless telecommunications. It is different from GSM (Global System for Mobile Communications). Typically, CDMA handsets differ from GSM handsets and don't feature the use of a SIM card, though handsets supporting both standards are also available. The data services offered by CDMA providers are also different from those offered by GSM providers because of the different access methods used.
With 91.2 million subscribers according to Mountain Wireless, Verizon is the largest mobile phone network in the U.S. It supports all 3 generations of CDMA: IS-95, 1x and EV-DO. According to the Verizon section of the Cell Phone Providers Review 2010, plans offered include prepaid, individual, family, business, international, data and mobile-to-mobile. Free nights and weekend minutes are also available from 9 p.m. until 6 a.m., which include unlimited free mobile-to-mobile, free domestic long distance calls and free text and picture messaging. Phones offered range from refurbished clamshell models to high-end Blackberry devices. The basic plan includes voice mail, numeric paging, caller ID, call waiting, call forwarding, walkie-talkie, and 3-way and conference calling.
Sprint Nextel is the third-largest U.S. mobile phone network with 48.1 million customers, as stated by Mountain Wireless. Sprint is the CDMA wing of Spring Nextel and offers plans such as individual, family and mobile-to-mobile, as well as the comprehensive premium plan "Unlimited Everything." The free night minutes run from 7 p.m. to 7 a.m. and include mobile-to-mobile, domestic long-distance, picture messaging and unlimited text messaging, according to the Sprint Nextel section of the Cell Phone Providers Review 2010. High-end iPhone and Blackberry devices as well as refurbished CDMA phones are some of the handsets offered with the plans; the basic plan includes voice mail, numeric paging, caller ID, call waiting, call forwarding, 3-way and conference calls. Virgin Mobile US and Boost Mobile are Sprint Nextel subsidiaries that use CDMA.
Serving 6.1 million subscribers across 26 states, U.S. Cellular is the nation's sixth-largest mobile service provider and runs on a CDMA network, as stated by Mountain Wireless. U.S. Cellular's plan offerings include prepaid, individual, family, data and business plans. Free nights and weekends package features free and unlimited domestic long distance as well as mobile-to-mobile minutes, text and picture messaging and free incoming minutes from 9 p.m. to 6 a.m. The basic plan offers voice mail, caller ID, call waiting, call forwarding and 3-way calling according to the Cell Phone Provider Review 2010.
According to Mountain Wireless, Cricket has 4.6 million subscribers in more than 25 states and offers mostly unlimited plan options (no time restrictions), making it an "on the go" mobile provider. Cricket offers unlimited local and national calling—and, in some plans, calls to Canada and Mexico as well. The Cell Phone Provider Review 2010 states that the basic individual or prepaid plans come with picture messaging and text included, as well as caller ID, voice mail, mobile web browsing and call waiting, on top of the unlimited calls.