Amazon has unveiled a new handheld device allowing users to wirelessly download and read books, magazines and blogs.

The $399 Kindle device downloads content from Amazon directly. The reader weighs 10.3 ounces and features a 6in screen.

Users can purchase content via Amazon's Whispernet EVDO network. The devices will connect to the Kindle Store where books, magazines and podcasts can be purchased and downloaded.

The Kindle Store uses a combination of purchase and subscription models. Books will be charged at a one-time fee, and best sellers and new releases are expected to cost $9.99.

Magazines and newspapers will incur a monthly subscription charge which will vary according to the publication. Users can also subscribe to Amazon-approved blogs at a cost of $1 a month.

Kindle enters an electronic book market which has not proved anything like as popular as digital music and video. The device's main competition will come from the Sony Reader.

But analysts have suggested that, if Kindle is successful, a new consumer market for e-books could arise.

"Amazon has a real chance to take e-books where they have not gone before: out of the enthusiast market and into the mainstream," wrote Jupiter Research vice president and research director Michael Gartenberg in a com pany blog.

However, Gartenberg warned that a price drop may be necessary to expand Kindle's reach.

"First devices will appeal mostly to road warriors who like to read and hate to carry paper," he wrote. "As prices come down, we will see more mass market adoption."

Ross Rubin, director of industry analysis at NPD Group, told vnunet.com that the device's direct connection to the Kindle Store could prove pivotal.

Unlike digital music or video players, where users will often import content already stored on their PCs or in CD collections, e-book readers rely entirely on what the user buys online.

"This is a product that, at least until now, has not resonated with hardcore bibliophiles. Some of that may have been that the reader required a PC to purchase content," Rubin said.

"[Wireless purchasing] is key in a product category that is so dependent on purchased content."