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Most service providers now offer Internet access and multimedia services using new high-speed data networks and selected phones. Sprint's Power Vision network and Verizon's V CAST network use an advanced CDMA format known as EV-DO (Evolution, Data Only) to boost transmission speeds. These networks comprise what is commonly known as 3G. Cingular uses an enhancement to its GSM network known as EDGE (Enhanced Data for Global Evolution). Some services, such as Verizon's V CAST video and Sprint's Music Store are only available through the enhanced networks. Other services, such as e-mail and Internet access, are available without having to access the enhanced networks, but tasks like Web browsing are much slower. One caveat: The newer networks aren't available in all areas of the country, so check your carrier's coverage maps before you upgrade your phone and plan. 

Among basic cell-phone features, look for a display that is readable in both low- and bright-light conditions. Be sure it's easy to see the battery-life and signal-strength indicators and the number you're dialing. The keypad should be clearly marked and easy to use. Single-key last-number redial is useful for dropped calls or when you're having trouble connecting. Most phones these days have voice dial, which lets you dial someone's phone number by speaking their name. But the number and name have to be in your phone's contact list, and you have to program each voice-dial name'Äîa time-consuming process. Voice command-enabled phones don't require training. You can dial anyone's number in your contact list, and even dial a number not in the list by speaking the digits.

In addition to ringing, most handsets have a vibrating alert or a flashing light-emitting diode to let you know about an incoming call, useful when you're in a meeting or at the movies. Handiest is an easy-to-mute ringer, which switches from ring to vibrate when you press and hold one key. Volume controls on the side let you change the earpiece volume level without moving the phone too far from your ear. You can't do that if the volume controls are on the keypad. A speaker phone boosts the earpiece volume and microphone sensitivity, so you can carry on a conversation without having the phone against your ear.

Some cell-phone models include a headset. That capability is sometimes demanded by various local laws for drivers using cell phones. A standard headset connector (also known as a 2.5-mm jack) is the most common type of headset connector. Phones with this connector are compatible with a wider variety of wired headsets. If you frequently use a headset but hate fussing with cords, consider a phone with Bluetooth voice capability, which allows you to use a cordless headset. Not all phones with Bluetooth are equal. Bluetooth data lets you transfer items like pictures and contacts to other Bluetooth-enabled devices like printers, PDAs, and computers. Bluetooth data capability is found on GSM phones but not always on CDMA phones.

Many CDMA phones have analog backup capability, which may be important if you travel through rural areas or places where your digital carrier doesn't provide service. Phones with analog capability can sometimes connect in places where digital-only phones cannot.

Phones vary widely in keypad design and readability of screen displays, as well as in the ease of using the function menu or performing such basic tasks as one-button redial and storage of frequently called numbers for speed-dialing later. It's important to handle a phone in the store before you buy, to be sure that its design and your fingers are well matched.

HOW TO CHOOSE

Begin by selecting a service. Finding good service where you want it can be a challenge. The best way is to ask your friends and business associates'Äîpeople who literally travel the same roads you do‚Äîhow satisfied they are with their cell-phone service. In addition, keep in mind that Verizon Wireless has consistently come in first in Consumer Reports satisfaction surveys and so is worth considering first, if it's offered in your area.

Choose a calling plan. You need to determine when and where you'll be using a cell phone most in order to select a plan that's right for you. As a rule, a national calling plan (which typically eliminates extra long-distance charges or fees for roaming away from your home calling area) is worth considering first, even if you don't travel often. With a regional plan, roaming charges can add up if you make calls too far away from your home. No matter which carrier you choose, take advantage of any trial period to test the service and sign up for the shortest contract available, typically one year.

If two or more family members use cell phones, consider a family plan that lets up to four people share a large monthly pool of minutes for a smaller additional monthly charge. If you aren't sure how many minutes of phone time you'll use in a month, choose a plan with more minutes than you think you will use. It's often better to let minutes go unused than to have to pay stiff per-minute charges if you exceed your allotment.

Select a phone. You can spend as little as $20 or as much as $600 on a cell phone. You need to begin your selection in the right price tier. Once you've settled on a price range, follow these steps:

First look for practical features. Cameras, games, music players, and the like are appealing, fun, and even useful for some people. However, features such as a folding case, volume controls on the side, and an easy-to-mute ringer will prove useful every day.

Hold the phone. In the store, take the phone in your hand and make sure you can comfortably access most keys with one hand. Try to make a test call and access the menu items on a working demo. We've found that phones with unconventional shapes can be difficult to use. So are keys that are small, oddly shaped, or arranged in unusual patterns, especially if you're trying to dial a number in dim light.

Check the display. Most color screens perform well in dim light, but some are hard to see in daylight. Try the phone outside or under bright light. In our tests, phones that display incoming and outgoing numbers with large black type against a white background were the easiest to read under most conditions. Also make sure indicators such as battery life and signal strength are clearly visible.

Check the return policy. Make sure you can return the phone if you're not happy with it. Some stores attach stiff service-cancellation fees on top of what a carrier may charge.

Don't buy phone insurance. All major cell carriers provide insurance policies that cover lost, stolen, or damaged phones, typically for about $4 to $6 a month, with a $35 to $100 deductible. But we don't think those are worth buying. Besides charging for premiums and deductibles, some insurance plans require you to fill out a police report. And damaged phones are often replaced with a refurbished phone, perhaps not even the same model as the original.