The Good:

• Ultra-slim profile
• Superb build-quality
• Decent feature set

The Bad:

• Less-than-perfect multimedia functions
• Hard to use ultra-thin keypad

This phone is all about Ultras. It's the clamshell member of Samsung's Ultra Edition family. It's ultra-thin at 9.9 millimeters thick when the phone's closed, meaning it will go well with slim formal clothes. It's got an ultra-bright and colorful screen. It's got ultra-dynamic interface animations. And generally, the Samsung SGH-D830 is ultra-responsive.

The smartphone is ultra-versatile. Crammed inside a package less than a centimeter thick are a 2.0 megapixel camera, music playback capability (formats supported MP3, AAC, and WMA), and ultra-easy-to-use Bluetooth. You can also make calls or listen to music with A2DP-enabled headsets. The built-in camera is ultra-decent. In well lit areas, it captures subjects well, saving stills with resolutions as high as 1600x1200. It surely won't appeal to professional photographers, but it's ultra-perfect for those everyday snapshots.

For such a thin mobile, build quality is ultra-impressive. The clamshell joint is snug and sturdy. The gadget survives a trip in the back pocket, probably because the rear battery cover is actually made of metal. Speaking of which, the battery lasts about two days of normal usage...if Bluetooth is used only when needed. Both wall sockets and powered USB sockets can charge the smartphone by the way.

Unfortunately, some ultra-annoyances keep the D830 from achieving must-buy status. Foremost of these are the ultra-thin buttons. The keypad is no doubt an engineering marvel, but it's just hard to use. It's hard to find the perfect balance between pressing too soft (no effect) or too hard (tires the fingers, and slows down typing). Even two weeks of practice fails to make the tapping experience any easier.

Music quality is ultra-disappointing, with weak bass and tinny treble. And since the earphones plug into the same proprietary socket the data cable and AC charger use, it's impossible test if the phone or earphones are at fault. As mentioned, the camera has no problems capturing well-lit subjects. For some reason though, videos max out at an ultra-measly 176x144 pixels. Browsing through a collection of large pictures is also ultra-slow.

The Samsung SGH-D830 is an ultra-marvelous phone. Despite its current status as the thinnest clamshell in the world, it boasts a surprisingly varied set of features. But it has its share of shortcomings, and the relatively high price may turn off casual users.

Update: I've written more on the D830's ultra-customizable tones.