Buying Cell Phones under 100$ is more than choosing a handset--you also have to pick a service provider, or carrier, as well. Because each carrier in the United States offers a different selection of technologies and services, so it's important to think about your needs when making a choice.
Wireless carriers in the United States operate over two different networks of Cell Phones under 100$: Code Division Multiple Access (CDMA) and Global System for Mobile Communication (GSM). Though each technology transmits voice and data, they do so in different ways, which makes them incompatible. As a result, you can't take a CDMA phone and use it on GSM or vice versa.
Wireless carriers in the United States operate over two different networks of Cell Phones under 100$: Code Division Multiple Access (CDMA) and Global System for Mobile Communication (GSM). Though each technology transmits voice and data, they do so in different ways, which makes them incompatible. As a result, you can't take a CDMA phone and use it on GSM or vice versa.
Of the U.S. carriers, AT&T and T-Mobile Cell Phones under 100$ use GSM while Sprint, Verizon, and smaller carriers such as such as MetroPCS and U.S. Cellular use CDMA. Though Nextel is part of Sprint, Nextel-branded phones use a third technology called iDEN, or Integrated Digital Enhanced Network.
CDMA coverage is very strong Cell Phones under 100$ in the United States, particularly in rural areas, but GSM service has a larger global footprint (it's the standard in Europe, for example) and GSM phones use the convenient SIM cards, which you allow you to, among other things, switch phones more easily. Also, when taken on a global scale, GSM users will find a wider selection of handsets.