The Eternity has all the hallmarks of a touch-screen phone. It has a rectangular candy bar shape with a slim profile (4.3 inches by 2.2 inches by 0.5 inch) and a large display. The Eternity is 3.88 ounces, a bit lighter than some of its counterparts, but it retains a sturdy feel in the hand.

The black color scheme is simple but attractive; we like the glossy material that surrounds the display and the shiny metal spines. Our only gripe concerns the plastic battery cover; a metal cover is preferable. At 3.2 inches the Eternity's display falls between the Instinct and the Behold in size. It should make it adequate for most users, whether you're browsing menus or typing on the virtual keyboard. It's also bright and vibrant with support for 262,000 colors (400x240 pixels). Photos and graphics were sharp and the text is readable. You can change the brightness, the backlighting time, and the font type. Below the display sit three physical keys: Talk and End buttons and a back key.

They're a tad slick, but it's a minor issue. The touch interface is responsive and easy to use, though you can adjust the calibration if you have problems. We had no issues selecting items and scrolling through long menus. The vibrating feedback is helpful, and you can adjust its intensity. Like the other Samsung phones in its class, the Eternity shows Samsung's unique and accessible TouchWiz interface. AT&T added some of its own widgets including a shortcut for the Mobile TV application. Check out our Behold review for a full description of TouchWiz. There's a second shortcut bar at the bottom of the display that gives one-touch access to the phone dialer, your contacts list, and the main menu. And speaking of which, the menu comes in an icon or list design. Both are intuitive with a variety of easily accessible features. The phone dialer has large alphanumeric buttons.

 You can access your contacts list and send a message with the touch of one shortcut. When on a call, it's just as easy to activate the speakerphone. The virtual QWERTY keyboard is similar to those on the other Samsung touch-screen handsets. It offers separate keyboards for letters and number/symbols but the Eternity adds a third keyboard for emoticons. Though all keyboards take full advantage of the display, here again the allotted space for typing your message is rather small. But on the upside, the dedicated punctuation keys are handy, and we like how easy it is to deactivate the predictive text and to change to French and Spanish menus. And thanks to the Eternity's accelerometer, you can change to the standard alphanumeric keypad or a graffiti application simply by rotating the phone. Though on the whole it's a user-friendly experience, we didn't like how you're restricted to using the alphanumeric keypad when entering message recipients. That keypad has dedicated shift and space keys, but we don't think you should use a multitap interface unless you absolutely have to do so.

On the left spine of the Eternity you'll find a volume rocker and combination headset jack/charger port. Of course than means you can only use one peripheral at a time, and the included headset uses a proprietary connection. On the right spine are a camera shutter and a key that activates a pop-up shortcut menu for the phone dialer, the music player, the main menu, the Web browser, and the messaging menu. Above those controls on the same spine is a 3.5mm headset jack. Though it's a welcome touch, audio from calls is not routed through this port. At the top of the phone is a dedicated power button/screen locking control. The camera lens sits on the back of the phone affording camera-like ergonomics. Unfortunately, the Eternity doesn't offer a flash or a self-portrait mirror. The Eternity phone book 1,000-contact phone book with room in each entry for multiple phone numbers, e-mails, and URLs. You also can add a street address, a company name and job title, a nickname, a birthday, and notes (the SIM card holds an additional 250 names). You can save callers to groups and you can pair them with a photo and one of 11 72-chord, polyphonic ringtones.

Though that's a paltry number of included ringtones, you can use your own audio files and MP3 tracks as tones. Other essentials include a vibrate mode, text and multimedia messaging, a calendar, a calculator, a notepad, a task list, an alarm clock, a world clock, a timer, a stopwatch, a currency and unit converter, and a speakerphone. For more discriminating users, the Eternity has full Bluetooth with a stereo profile, a file manager, a voice recorder, USB mass storage, and instant messaging. That's not a bad assortment, but Wi-Fi and voice dialing are glaring omissions. Also, the e-mail situation isn't ideal for business users. Though AT&T's Mobile e-mail service offers access to a variety of POP3 services, it is a Web-based application that doesn't sync automatically. What's more, IMAP4 is largely unavailable. The Eternity offers basic PC syncing for photos, music, and other date files, but it can't sync with Outlook e-mail, calendars, and contacts. You can exchange contacts with third-party syncing software, but that will require an additional investment. The full HTML browser is similar to the Behold and the Instinct. Of course, it can't handle Flash animation, but it renders most pages well. The onscreen controls are intuitive, but, as we've said before, we much prefer the iPhone's multitouch interface to using a magnifying button to zoom. Scrolling through lengthy Web pages can take a lot of finger swiping, but it's not unlike other touch-screen phones. Also, it can be difficult to select links on crowded pages, but that's not unusual, either.

 We tested the quad-band (GSM 850/900/1800 1900; UMTS 860/1900) Samsung Eternity in San Francisco using AT&T service. Call quality was mostly satisfying. We enjoyed a clear signal with little static or interference. Our callers' voices sounded natural, but we noticed that the sound became slightly distorted at the highest level. It wasn't a huge deal, but the sound had a muffled tone. Yet, because the volume level was a tad low, we had to turn up the sound pretty high in order to hear in noisy locations. There was also a slight amount of GSM buzz, but it was minimal. Bluetooth headset calls were fine as well. On their end, callers said we sounded fine most of the time. They also had trouble hearing us at times; a few said the phone picked up a lot of wind noise, but most reports were positive. Similarly, automated calling systems could understand us, but only if we were in a quiet room. Speakerphone calls had about the same audio quality. The volume could be louder and we had to speak close to the phone to be understood. The speaker's minimal low output also is apparent when listening to music. A headset will provide the best experience. The 3G connection was just above average. When using the Web browser, some pages took more than a few seconds to load, and at times the pages were a tad sluggish when we were scrolling around. Streaming videos also took longer to load than we expected, but they performed well once they were up and running. Our videos never froze or dropped the connection. The Eternity has a rated battery life of 5 hours talk time and 10.42 days standby time. Our tests reveal an impressive talk time of 14 hours and 18 minutes. According to FCC radiation tests, the Eternity has a digital SAR rating of 0.194 watt per kilogram

Our unlocked GSM cellular phones are only designed to work on GSM networks Only! (such as Cingular, T-Mobile, and others in the U.S.; and Fido and Rogers in Canada).