The Lumia 710 represents Nokia's first Windows Phone 7.5 smartphone in the U.S., despite the fact that the higher-end Lumia 800 model has been available in other parts of the world for some time already. It shares a number of features with its higher-priced brother (mostly under the skin), but its low-cost roots can be quite evident in crucial areas like the phone's display and build quality.

Thanks to a fast processor and Windows Phone's attractive and snappy interface, the Lumia 710 is no slouch when you use it, and the phone benefits from solid call quality, decent battery life, and a usable camera. Read on to see whether the Lumia 710 can make a splash in the crowded U.S. smartphone market, or if it just another forgettable, entry-level device.

Hardware

The Lumia 800 is one of the most attractive and striking smartphones to come to the market in recent years (and top-notch build quality to go along with that). Unfortunately, the Lumia 710 does not share this particular trait, as it features a more pedestrian design and significantly cheaper-feeling materials.

The Lumia 710 has a 3.7-inch, WVGA (480 x 800 pixel) display with Nokia's ClearBlack branding. Unlike the AMOLED display on the Lumia 800, the LCD display on the 710 does not have endless, inky blacks and fabulous viewing angles. Colors are accurate, though, and the display performed well enough in direct sunlight. The traditional, flat design of the 710's display does not invite the user to swipe their finger over the screen in the same fashion that the Lumia 800's curved display does, but touch responsiveness was accurate.

Instead of using capacitive keys for the standard back, Start, and search keys for Windows Phone 7.5, the Lumia 710 opts for a single, plastic bar that encompasses all three buttons into one unit. This proved to be an annoyance for me, as the large button was not as easy to activate as a capacitive button and required more attention and force than should be required. The areas of the bar for each action are back-lit, but the light does not stay on for as long as I would like.

The Lumia 710's button problems don't end with the front of the phone, as the volume rocker and camera key on the right edge are very mushy and don't provide much feedback. The camera key, in particular, is quite hard to use, as it is very difficult to determine when you have pushed it down completely. The top of the phone is home to both the micro-USB charging/syncing port and the 3.5mm headphone jack. It is also where the power/sleep/unlock key is located. Thankfully the power button doesn't suffer from the same issues that plague the hardware buttons elsewhere on the device.

The back of the Lumia 710 is coated with a soft-touch rubber that provides a good grip when holding the phone. Unfortunately, it also attracts finger prints and pocket lint far more than other materials, forcing a particular person, like myself, to constantly wipe it down. The rear cover on the Lumia 710 is removable, and users can swap out the battery if they desire. Nokia is also offering replacement covers in a variety of colors, so owners can personalize the 710's look. The back of the phone is home to a 5 megapixel camera and LED flash, as well as a surprisingly loud and clear external speaker. T-Mobile is offering the phone in a white color scheme, but my review unit was a staid, black on black.

Like most Windows Phone 7.5 devices, the Lumia 710 does not support microSD cards, so you are stuck with on-board memory for picture, image, video, and app storage. And in the case of the Lumia 710, that storage is rather limited. The spec sheet indicates 8GB of internal storage, but the actual amount available to the user out of the box is closer to 6GB. Owners might want to take advantage of the various streaming music services available to the Windows Phone 7.5 platform and get in the habit of moving their media off the phone fairly regularly if they opt for the Lumia 710.

The Lumia 710 won't win any awards for being the thinnest smartphone on the market at 12.7mm (0.5in), but its curved edges do help hide its girth. It is also quite light at 125g (4.4oz), likely thanks to the liberal use of plastic in its construction. At 119mm (4.68in) tall and 62mm (2.45in) wide, the 710 is just a tad taller and wider than an iPhone 4S.

Usability

The Nokia Lumia 710 is powered by the same 1.4GHz Qualcomm processor and 512MB of RAM as the Lumia 800, as well as the Samsung Focus S, Focus Flash and HTC's Titan. As with the other devices, this processor and RAM combination allows for a swift user experience, and there is very little lag throughout the system. The Windows Phone interface gets out of your way easily, and apps are quick to open more often than not. Scrolling through lists is fast in all of the native apps on the phone, but as we have seen with all Windows Phone from the outset, third-party apps still struggle with smooth scrolling.

While Windows Phone 7.5 presents an enjoyable experience for the most part, there are areas that still cause consternation for me. With the 7.5 Mango update, Microsoft changed the behavior of the search key so that it opens up a Bing search no matter which app you happen to be in. It does not default to a search function within the app itself, but instead kicks the user out and opens up a web search. I find that the older functionality of the button (defaulting to in-app search, for example, searching within email) was more intuitive and efficient. The live tile system is useful and innovative, but if an app is not one that you want pinned to the home screen at all times, the only way to access it is by scrolling through all of the apps that are installed on the phone. Windows Phone 7.5 does offer a search function in the app list, but the ability to group apps together in relevant folders would be greatly appreciated.

The People hub that groups all of your contacts and integrates with social networking services such as Facebook, Twitter, LinkedIn, and Windows Live is slick and informative, but it could be even better if it incorporated audible/vibration alerts for various notifications and the private messaging services of each social network. Until those features are added, users still have to rely on third-party apps for a full social networking experience.

Overall, the Nokia Lumia 710 offers a pleasant experience, though the hardware issues with the buttons and some of the limitations of the Windows Phone 7.5 operating system hold it back from being stellar.