Four of the five top selling mobile phones on the market today are smart phones, according to a report by NPD group. So, smart phones rule, right? Not quite.

Turns out that the number 1 best selling phone is the not-so-smart Motorola Razr. This ancient (in mobile phone years) "voice-centric" clamshell design has been the best selling phone since at least 2005 when NPD Group first started conducting research on mobile phone sales.

Why? Mainly because of cost and the fact that multiple carriers who offer the phone. In many cases the phone is offered free with a service contract, and it is offered by all four of the top tier services providers in the U.S., as well as by many smaller regional carriers and independent dealers. Smart phones like the iPhone 3G and the Blackberry Pearl usually are offered by a single carrier under and exclusive arrangement.

The diversity of phones on the NPD best seller list (Razr, iPhone, Blackberry Curve, LG Chocolate, and the Blackberry Pearl) reflects the continuing diversity of consumer tastes, according to NPD Group. Nevertheless, the popularity of the inexpensive, voice-centric Razr suggests that a very large part of the market still seeks simple voice communications and is not willing to pay for extra services and features.

Read more coverage of the NPD report at: http://www.rcrwireless.com/article/20081008/WIRELESS/810079987/-1/rss01#