We've so loved the Sony Ericsson Walkman phones that when a new one comes out, we're always eager to get our hands on it. And with the company's latest model, the W850i Walkman, Sony Ericsson managed to surprise us. After producing Walkman models in candy bar, flip phone, and swivel designs, Sony Ericsson chose to cast the W850i in a very trendy slider design. Overall, its new venture is effective, but the W850i stumbles hard with its confusing and poorly designed navigation controls. Features and performance are about what you'd expect for the Walkman line, which is a good thing, but we're tempted to stick with the more intuitive W810i. The W850i is pricey at S$848 (US$539.51) and S$598 (US$380.46) with a two-year contract.

Design

Like Nokia, Sony Ericsson isn't quick to jump on the latest design trend, so the company did catch us somewhat off guard when it chose a slider design phone for the W850i. Overall, the sliding mechanism is solidly constructed, and we had no trouble moving it up and down with one hand. Yet it wasn't so loose that it slid up when we didn't want it to. As with other slider designs, the W850i doesn't cradle your head when positioned against the ear, but it's still comfortable to hold while talking. It's not very compact either at 98 x 47 x 21 mm and 116g, but its bulk is not bothersome.

Despite being a tad boxy, the W850i is still attractive and sporty. We also like that it comes in white and black (we reviewed the black version). Dominating the front face is a sizable two-inch (24x320 pixels) display. Like most Sony Ericsson displays, the 262,144-color screen is easy on the eyes and displays everything from photos to games to the user-friendly menus beautifully. You can change the brightness and the clock size but nothing else.

Below the display are the navigation controls, which threw us for quite a loop when we first started using the phones. Sony Ericsson has a mixed record on controls and buttons, and we're disappointed the company is slipping back to old habits. First the good points: Though they blend in with the surface of the phone, the black soft keys are large and quite tactile. In standby mode, they open the calls list and main menu.

Now, the bad points: Between the soft keys is a dedicated Walkman control that's used to activate the music player. Though it's easy to identify because of its bright orange color, the Walkman button has a long thin shape and is squashed next to a raised silver bar. Unfortunately, those two features make the control very difficult to press unless you have nails. The main navigation array that sits below the display has such an unintuitive design, we can't imagine what Sony Ericsson was thinking when it rolled this one out of the design lab. Instead of a traditional toggle or a joystick, the W850i has a recessed OK button surrounded by four pressure points for each direction (up, down, left, right). Since the pressure points are completely flat with the surface of the handset, we had difficulty knowing where to put our finger. We got used to it eventually, but even then the pressure points had a cheap plastic feel. And because the backlighting on the pressure points is so dim, dialing in the dark wasn't easy. The OK button has a more tactile "push" feel, but our finger kept sliding off it because it's recessed. A raised OK button would have been a much better arrangement.

The keypad buttons behind the sliding face are better than on most slider phones. Though they're flush with the handset, they have a beveled design that makes them quite tactile. They also are big enough and are spaced far enough apart. Other controls consist of a dedicated clear button, a Web browser shortcut, and a key that opens a user-programmable shortcuts menu. Though all the keys are useful, they could have been much bigger. The navigation pressure points double as user-defined shortcuts as well, and the OK button acts as a play/pause control when the music player is open.

A volume rocker, a camera shutter, and the infrared port are located on the right spine of the phone. The toggle, while a bit slippery, is easy to find when on a call. It also acts as the zoom control for the camera. The camera lens, flash, and self-portrait mirror sit on the back of the phone, which like on most Sony Ericsson Walkman phones, is designed to look like a real camera. A dedicated power button and the Memory Stick Duo slot sit on the top of the phone, and a single port for the charger and the headset sits on the phone's bottom end.

Features

The W850i offers an attractive feature set that's comparable with other Walkman phones'. But first, the basics. The phone book holds an impressive 1,000 contacts with room in each entry for five phone numbers; work title and company name; a birth date; additional notes; and e-mail, Web, work, and home addresses. You can save 250 more names to the SIM card. You can assign contacts to a caller group and pair them with a picture or one of 23 polyphonic (40-chord) ring tones for caller ID purposes. A vibrate mode, conference calling, voice dialing, and a speakerphone (usable only after you make a call) round out the calling options. Organizer features include an alarm clock, a calendar, a task list, a notepad, a calculator, a timer, a stopwatch, and a code memo for storing passwords and other secure information. Finally, the camera flash doubles as a tiny flashlight. Though it's not suitable for finding your way through the woods at night, it's bright enough to help you find your keys in a dark room. Alternatively, you can set it to blink rapidly in SOS mode.

Like the W810i, the W850i comes with a full assortment of business-friendly features. Onboard is full Bluetooth for headsets and data transfers, an infrared port, text and multimedia messaging, e-mail, USB cable support for data transfers, and PC syncing for contacts and other files. In addition to sending files or connecting to a headset, you can use the Bluetooth feature as a remote control to connect with another Bluetooth devices. The W850i also makes it easy to pass on your contact information by allowing you to beam an electronic business card with your vital data to a contact. And for an impromptu dictation session, the phone comes with a recorder for both voice memos and calls; length is limited by available memory.

As with the other Sony Ericsson Walkman phones, the W850i's music player is the phone's star attraction. The features, controls, and interface are similar to predecessors', but with a few changes. A simple black background replaces the familiar orange skin, and you can choose to display album art or graphic visualizations when your music is playing. Opening the player takes you directly to the main menu, where you can organize music by artist, track name, or playlist. Settings include album/song shuffle and loop, an equalizer, and stereo widening. Switching between the cell phone and the music player is seamless, as music automatically stops when you receive a call. Hang up and press the dedicated music key, and your song picks up from the point you left off. There's an airplane mode that lets you listen to your tunes in flight with the cell phone turned off, and you can minimize the player while using other functions. You can also set the navigation controls to show a bright orange backlighting, but it turns off when the player is off.

Music capacity is limited by the available memory, but internal space is just 16MB - skimpier than we would have liked for a media phone and less than for most previous Walkman phones. And keep in mind, it's shared with other applications, so your actual storage space may be less. We recommend investing in a Memory Stick Duo for extra space. Our test phone came with a 1GB card, but the slot can accommodate higher-capacity cards. Fortunately, you can set tracks as ring tones. You can send tunes via e-mail, multimedia message, Bluetooth, or infrared port. You also get an FM radio with 20 presets, though you must use it with a headset, which acts as an antenna. You can set it to automatically scan and program Radio Data System info from stations that digitally broadcast their names and call letters. The W850i also comes with a Track ID application that you can use to identify music slips from FM radio stations.

Though it has a 2-megapixel camera, the W850i takes pictures in just three sizes: 1,632x1,224, 640x480, and 160x120. As with the company's other 2-megapixel shooters, we were hoping for more choices. That said, other options are plentiful. There are Normal, Panoramic, Frames, and Burst shoot modes; a 4X digital zoom (not usable at the highest resolution); night mode; a flash; a time-and-date stamp; a self-timer; Black and White, Negative, and Sepia picture effects; white-balance settings; Normal and Fine picture-quality modes; and four shutter sounds, though no silent option. The MPEG-4 video recorder takes 176x144 clips with sound to any length that the available RAM will permit. Clips for multimedia messages are capped at 30 seconds. After you're finished shooting photos or videos, you can edit your work with the included Photo DJ and Video DJ applications. There's also a fun face-warping tool for turning your friends' likenesses into silly art. Photo quality is very sharp and ranks as some of the best we've seen on a camera phone. Colors are bright and object outlines distinct. Videos, on the other hand, are satisfactory but somewhat choppy and pixelated.

You can personalize the W850i with a variety of themes, wallpaper, and screensavers. As always, you can purchase more options and ring tones from Sony Ericsson via the WAP 2.0 wireless Web browser. Alternatively, the phone comes with a Music DJ application for composing your own ring tones. Gamers can enjoy two Java (J2ME) titles, QuadraPop and Juices, with additional titles available for purchase.

Performance

We tested the triband Sony Ericsson W850i (GSM 900/1800/1900) world phone and found the call quality quite good, though voices sounded a bit hollow and the volume could be higher. On their end, callers could hear us plainly and said our voice wasn't distorted. They could tell we were using a cell phone, but that's not unusual. Speakerphone calls were satisfactory, with loud volume. Callers could hear us fine but it's best to make speakerphone calls in quiet environments. Overall, we give the call quality a thumbs-up. UMTS support is included as well, but at present, the phone is incompatible with UMTS networks in the United States.

The included PC Suite software and USB cable is the main conduit for loading the music on the phone. The software is easy to use and music quality on the W850i is fantastic. Audio is clear and crisp and has plenty of volume. The W850i won't replace a stand-alone MP3 player just yet, but it does the job admirably for short stints.

FCC radiation tests, the Sony Ericsson W850i has a digital SAR rating of 0.6 watt per kilogram.