Like the K790a, the K800i sports a simple candy bar form factor that's roughly rectangular in shape but still sleek and stylish. What's more, the black-and-gray color scheme accurately reflects the high-tech features inside. It's far from compact (4.1 by 1.9 by 0.9 inches; 4.1 ounces) but with its solid construction and comfortable feeling in the hands, it's a worthy trade-off.
The K800i has the K790a's same brilliant 262,144-color display that measures two inches diagonally (240x320 pixels). Below the display is the navigation array, which is similar as well. The five-way joystick doubles as a shortcut to four user-defined functions, while the two soft keys open the recent-calls list and the main menu when the phone is in standby mode. There are also dedicated Back and Clear buttons, a key that launches the Web browser, and a nifty control that opens a submenu of user-defined shortcuts and a list of upcoming calendar events. Overall the navigation controls were tactile and easy to use, but they are somewhat squashed together. The backlit keypad buttons were a nice change, however, from previous Sony Ericssons. Rectangular in shape, they are large enough for most hands and are raised just above the surface.
A music player button and the Memory Stick Micro slot sit on the left spine, while the right spine holds a volume rocker and a camera shutter control. The camera lens and self-portrait mirror sit on the back of the handset behind a sliding cover. Above is the large, high-quality flash, while a small speaker is next to the camera lens.
The phone book holds a respectable 1,000 contacts with room in each entry for five phone numbers, Web and e-mail addresses, a work title and company name, work and home street addresses, a birth date, and notes (the SIM card holds an additional 250 names). You can organize contacts into groups and pair them with photos for caller ID. You can pair contacts with one of 16 72-chord polyphonic and MP3 tones. Other essential offerings include a vibrate mode, text and multimedia messaging, an alarm clock, a calendar, a task list, a timer, a stopwatch, a calculator, a notepad, and a voice memo recorder (space is limited by the available memory).
The K7800i also comes with a wealth of business-friendly features. You'll find full Bluetooth for connecting to a wireless headset or sending files or your electronics business card to another Bluetooth device. And like with many other Sony Ericssons, you can use the phone as a modem and use the Bluetooth feature as a remote control to connect with other Bluetooth devices. Other high-end goodies include a speakerphone, an RSS news reader, an infrared port, PC syncing for contacts and other files, USB cable support, e-mail, voice dialing, and a code memo for storing passwords and other secure information. And because the phone supports UMTS networks, you can watch streaming video.
Like the K790a, the 3.2-megapixel K800i Cyber Shot is one of the most advanced camera phones we've reviewed. Camera features were the same on both phones. You can take pictures in four resolutions, from VGA up to the full 3 meagpixels, and choose from two image quality choices. Other notable offerings include a panorama mode, red-eye reduction, spot metering, a macro setting, and image stabilization (see the K790a review for a full list of the camera features). The camcorder, which is also similar, takes MPEG-4 clips with sound in one resolution (176x144). And here again the remarkable Xenon flooded our photos and videos with light even in dim situations.