how to decide service provider's to cell phone.

Buying a mobile phone is a matter of choosing a phone - you must also select a service provider or company, too. Each carrier in the United States offers a different selection of technologies and services, it is important to consider their needs when they take a decision. Therefore, the choice of a company is the first step in the process of buying a mobile phone.
Technology Twist
Cell phone companies in the U.S. operate on two different networks: Code Division Multiple Access (CDMA) and Global System for Mobile Communications (GSM). Though each technology transmits voice and data, they do it different ways, making them incompatible. Therefore you can not take a CDMA phone and use it on GSM or vice versa.
U.S. airlines, AT&T and GSM T-Mobile use while Sprint, Version, and smaller operators such as Metro PCS and U.S. Cellular use CDMA Although a portion of Sprint Nextel, Nextel brand phones use a technology called iDEN third, or integrated Digital Enhanced Network.
CDMA coverage is very strong in the U.S., particularly in rural areas, but the GSM service has a larger global footprint (which is the norm in Europe, for example) and GSM phones use SIM cards practice, which allows, among other things go easier on your mobile . In addition, when they are taken on a global scale, GSM users will find a wide selection of phones.
In this spirit, if you travel overseas frequently or you enjoy using your phone often for the latest model available, GSM is the best option. Not all GSM phones in foreign countries, however, so make sure to read CNET's quick guide to the mobile world. But if you're calling for the most part in the United States, then CDMA is an equally good alternative. In addition, some CDMA phones now also support GSM networks for international use.
Besides technology, other factors play a decision. You must first find out which company has the service committee plans cheapest and best phones. The quality of customer service is another factor, but it may be difficult to assess in advance. How to know the advantages and disadvantages of each carrier is not easy, we invite you to look into service providers in our rapid cell phone companies. Besides the major operators, you can also consider the Mobile Virtual Network Operator (MVNO) businesses that serve a particular demographic group or lifestyle. For example, the Virgin Mobile designed for younger users while Boost Mobile is focused on urban users who want advanced functionality. MVNO does not operate its own cellular network, but the space rent network rather than domestic firms.
In the end, but you must base your decision that carries the best reception in your area. Because evaluating wireless coverage requires some experience with the network in different physical locations, CNET does not rate wireless carriers, you can buy, we have partnered with a unit root to create a tool to determine the top company in your neighborhood, travel or workplace. Be sure to check it out. Word of mouth is also useful when selecting a supplier. From the reception varies depending on the location, ask friends and family of each company they use. In addition, since there is no substitute for real world experience, to borrow a friend's phone, and test it at home and at work. Remember that companies have a grace period where you can test the service and return the phone without invalidating the contract. But if they get a phone and cancel a contract, you may need to pay for calls during the operation.