Nokia has unveiled a pocket-size web browser for wireless broadband networks. This is the Finnish firm’s first Linux-based device and its also the first product without a built-in mobile phone. The new device, dubbed the Nokia 770, has a 4-in horizontal touch screen that can display normal Internet pages and will sell for around $350.

The product marks a significant strategy expansion for Nokia, which is venturing outside its mainstay cellular phone business. Nokia aims to sell the device through broadband home Internet providers and directly to consumers via its Web site. The device is consumer device is targeted for home use that can be used at wireless hot spots. The product will run entirely on open-source software, used in desktop computers, marking more unchartered waters for Nokia.

The pipeline include upgrades by early next year to enable voice-over-IP calls and instant messaging. VoIP phone calls from the device may cannibalise cell phone voice revenue from Nokia’s main customers, which include all of the world’s biggest mobile operators.

Nokia also plans to launch and support an open-source community Web site, encouraging software developers to hack into the device and improve the product. Nokia aims to be competitive by implementing innovations ahead of competitors while benefiting from its large scale, it makes one of every three mobile phones sold in the world.

Consumers will be able to store content downloaded from the Internet on removable MMC memory cards, or transfer it to a desktop computer with a USB connection or Bluetooth. This new device, which took Nokia two years to develop, is a stab at the market for portable computers.