PC World — T-Mobile is launching a new phone-- the Sony Ericsson Equinox. Unlike most headline-making mobile phones, the Equinox is not trying to be the next iPhone-killer. The Equinox isn't even trying to be a smart phone.

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The Equinox is a feature phone, which is a polite way of saying its not a smart phone, which is a nice way of saying it's a dumb phone. The Equinox looks like it might make the feature phone fun again though. Just because your phone doesn't have an app for that doesn't mean it can't have some cool features.

The Equinox has a 3.2 megapixel camera, built-in FM radio, Bluetooth connectivity, and an integrated GPS. The device has colorful lights which flash for incoming calls and can be coordinated with the T-Mobile My-Faves list so that each individual on your list can flash their own unique color.

One of the upsides to a feature phone is that you aren't obligated to subscribe to an expensive data plan in addition to the monthly service plan from the wireless provider. The tradeoff though is that most feature phones lack anything but the most rudimentary tools like a calculator, or an alarm clock. The Equinox puts some excitement back in the feature phone and delivers more compelling features without the smart phone.

The Equinox is a divergence from other recent additions to the T-Mobile portfolio. The Samsung Behold II and Motorola Cliq are both Android-based smart phones that will compete against devices like the Apple iPhone.

T-Mobile is the low-man on the wireless provider totem pole, lagging a distant fourth behind companies like Verizon and AT&T. It has been more aggressively expanding its portfolio though and there have been rumors that it could be bought, or even that it could buy rival provider Sprint.

The Equinox is no iPhone, and its not a potential threat to the iPhone like the Verizon Droid . But, the Equinox could be a success because it provides an alternative for cost-conscious user or users who reject the idea that the mobile phone should be a mobile personal computing and communications device. T-Mobile is offering the Equinox for only $50 (and without the data plan) on a 2-year contract.

T-Mobile has suffered from negative publicity lately related to the Sidekick data debacle. Arguably, T-Mobile had little responsibility in the matter, but it still took most of the heat. Exciting new devices like the Equinox can help T-Mobile shift the story and put the focus back on innovating and competing to claw its way out of fourth place.

Tony Bradley is an information security and unified communications expert with more than a decade of enterprise IT experience. He tweets as @PCSecurityNews and provides tips, advice and reviews on information security and unified communications technologies on his site at tonybradley.com.