The Big Picture
Bluetooth technology lets two devices talk to each other wirelessly over low-frequency radio waves in the 2.4GHz range. Both devices, such as a phone and a headset or a phone and a speakerphone, must be Bluetooth-enabled.
The devices connect through a process called pairing. To start pairing between a headset and a phone, you use your Bluetooth phone's interface, making sure that the headset is turned on and in pairing mode. The phone then searches for and locates the headset. To establish a connection, depending on the version of Bluetooth that your phone and headset support, you may need to enter a PIN on your phone's keypad; afterward, your phone will recognize the headset. And, you hope, the devices will talk--nicely--to each other. The process is identical when you pair your phone with a speakerphone. (For more details about Bluetooth specifications, see "The Specs Explained.")
Manufacturers and Flavors
Headsets: You'll encounter a huge variety of Bluetooth headsets on the market. A monaural (or mono) unit has a single earpiece and a design that puts the microphone close to your mouth. Stereo headsets or headphones come with two earpieces. Though they bring you stereo sound and let you listen to your tunes as well as make calls, their microphones typically sit much farther away from your mouth.
You can find models from traditional headset makers (such as GN Netcom--the name behind the Jabra products--and Plantronics), cell phone manufacturers (such as Motorola and Samsung), and Bluetooth-only companies (such as Aliph and its Jawbone line). At the low end, Bluetooth mono headsets start at about $15; at the high end, you can expect to pay at least $100. Stereo headphones can be $50 to $200, sometimes more.
As far as headset design and style go, take your pick: over-the-ear or earbud (some do both); silver, gold, candy-colored, black, or gray; sleek or boring; bulky or discreet; long or short; lightweight or superlight. Over-the-ear (aka earhook) headsets can have wide, loopy hooks or thin, narrow ones; they can be plastic, rubberized metal, or leather, too. Some headsets have earbuds that are completely round, while other buds have tips that protrude. Some stereo headsets have earpads that sit on the outside of your ears and are connected either by a neckband or a cord.
Headset makers handle the arrangement and feel of the function buttons differently, too. Some buttons are recessed, others are raised, while still others are flush with the headset's surface. Some buttons sport notches or markers; others lack indicators entirely.
In-car speakerphones: You'll find plenty of Bluetooth car units--from companies such as BlueAnt Wireless, Jabra, LG Electronics, Motorola, Parrot, and Plantronics--that are portable and ready to pop into your car. Expect to pay about $20 or more for an entry-level model or an older unit; from there, prices can go up to $100. You position the speakerphone unit on your sun visor, your windshield, or on your dashboard. (Note: In some states it is illegal to attach any item to your windshield.) In addition to managing calls, some speakerphones let you stream music and transmit audio through your car stereo.
Many brand-new cars have Bluetooth kits factory-installed. If yours doesn't, you can have a professional wire up your car with a speakerphone.
Performance and Packages
We'd like to say that these days call quality through a Bluetooth headset or speakerphone is consistent and comparable to--or better than--what you get from a cell phone on a good day. But it isn't. In our testing, even the best-sounding headsets overall still had their off moments, producing faintness, voice distortion, echoes, and disappointing background-noise cancellation, for example. And judging from our tests of car speakerphones, their audio quality is even less impressive. Interference of various kinds made a regular appearance. Car kits don't handle background noise as successfully as mono headsets do, either. Furthermore--and not surprisingly--voice commands ("Call Julianne mobile," for instance) work considerably better when you're wearing a mono headset, since the attached microphone is positioned close to your mouth.
When you're considering battery life, expect to see a wide range. Depending on the manufacturer, advertised talk times for mono headsets start at about 4 hours and go up to 9 hours. Standby times start at about 100 hours and extend to about 250 hours. For speakerphones, talk times start at about 14 hours and extend to about 20 hours; standby times start at about 300 hours and go up to a whopping 800 hours. With solar-powered speakerphones, theoretically, you can hope for unlimited talk and standby times, as long as your device can soak up lots of sunlight daily.
In a perfect world for headset makers, people's ears would be identical. They aren't, of course, and that's why we prefer that headset bundles include multiple options to help you find a good fit. Some manufacturers are generous with their goodies, providing small, medium, and large earbuds, along with an additional earhook or two. Others give you an AC charger and a user guide, but nothing else in the box.