Despite having been marketed exclusively to enterprise users in the past, Nokia has made a concerted effort in recent history to expand the appeal of its Eseries line. Sleek new designs, slender profiles and a more complete feature set have replaced boring and bulky Eseries handsets of years past.

The E71 ushered in Nokia's new Eseries breed and the trend has been carried forth quite well by the likes of the E63, E66, E75 and others. The Nokia E55 is the Finnish handset maker's latest effort to woo prosumers with a stylish design and where hardware is concerned, the E55 delivers in spades.

From the slender 9.9mm-thick case to the handsome blend of metal and hardened plastic, this phone is certain to turn heads. The Nokia E55 also weighs a mere 95g, making it one of the more pocketable handsets in Nokia's arsenal. Unfortunately, the company's effort to produce a svelte stunner has resulted in decreased usability and an overall humdrum user experience.

Form outweighs function

Starting with the handset's most distinguishing characteristic, its compact QWERTY keypad, form outweighs function by leaps and bounds. The compact QWERTY layout has been a polarizing keypad configuration ever since it was first popularized by the BlackBerry Pearl line. In the E55's case, letters are placed in pairs and spread across 14 keys.

Characters and formatting functions are then spread across the remaining six keypad buttons, including a space/zero button that is equal in size to the rest of the buttons instead of being a bit wider as it is on most keyboards. The handset relies on predictive text input to speed up the text entry process, though typing can be a hassle when entering URLs in the Web browser or in other areas where predictive input is not available.

While Nokia's T9 text prediction is actually quite good, small buttons and a lack of adequate tactile response makes typing a bit of a chore compared to the solid keypad found on the BlackBerry Pearl or even standard QWERTY offerings from Nokia like the E71.

Strangely, the zero/space key has almost no tactile response at all; the user must constantly constantly shift his or her eyes to ensure that spaces between words have been registered by the phone. Needless to say, this can be annoying at best and for heavy messaging users it may very well be a deal breaker.

The standard Eseries key cluster is found above the compact QWERTY keys, and includes the directional pad, select button, soft key buttons, call controls, backspace button and three shortcut keys for messaging, calendar and home. While the brushed steel look of the cluster surface is certainly pleasing to the eye, the device's narrow facade translates to reduced button size and an abundance of accidental key presses.

The S60 OS is showing its age

Moving on to the handset's operating system, the E55 provides the quintessential Symbian experience the world has been all too familiar with for years. Nokia's mouthful of an OS, S60 3rd Edition Feature Pack 2, is the weapon of choice and while it is quite flexible and usable, it is also very boring and stale compared to more modern options such as Android, webOS, iPhone OS and even Nokia's new Maemo 5 OS.

The phone's 2.4" 320 x 240 pixel QVGA display doesn't help matters at all; pixilated icons and miniscule, jagged letters age the OS considerably. Sub par screen resolution is a common problem amongst Nokia's mid-range handsets of course, so owners of previous Nokia handsets may not take issue. That said, the display is shameful compared to larger high-resolution displays that are becoming more and more common on mobile phones.

It's not all doom and gloom, however. The Nokia E55 packs all of the functionality smartphone users could hope for. Nokia messaging provides a solid email experience, now complete with HTML rendering, and support for Exchange Activesync, while Lotus Notes is sure to please business users.

Beyond PIM, the S60 platform is still the most actively developed mobile OS outside of the iPhone OS. If there is any desired functionality the E55 is missing out of the box, there are almost certainly a variety of applications that will fill the gaps. When it comes to using all of the great apps available for the S60 OS, the 600MHz ARM 11 processor makes the handset a multitasking monster, allowing users to quickly and easily switch between apps with little or no lag.

In terms of connectivity, Nokia has you covered: The E55 supports Wi-Fi (802.11b/g), Bluetooth 2.0, GPS, FM radio, quad-band GSM/GPRS/EDGE and dual-band WCDMA with HSDPA support up to 10.2Mbps alongside HSUPA support up to 2Mbps. On the right network, the E55 may very well move files faster than some land-based broadband connections.

The sleek handset falls a bit short on the multimedia front, simply because the small QVGA display is hardly conducive to watching videos. On the music side of things however, Nokia's Music Player app, a giant 1500 mAh battery and a 3.5mm audio jack make the handset a very adequate portable music player.

The 3.2 megapixel camera is full of features, while dedicated zoom and image capture buttons make picture snapping fast and easy. Mobile gaming fans won't be overly pleased with the cramped keypad or the poor display, but the E55 is certainly capable of hosting a quick game of Sodoku or Texas Hold'Em during a commute.

The E55 comes with a 2GB microSD card, stereo headset, microUSB cable, microUSB wall charger and a charger adapter for those who still have older Nokia chargers lying around. It also comes with a free 60-day trial of Files on Ovi (cloud file storage) and a 10-day trial of Nokia maps, Nokia's voice-guided navigation solution.