Nokia announced a pocket-size Web browser for wireless broadband networks, the Finnish firm’s first Linux-based device and its first portable product without a built-in mobile phone. The Nokia 770 Internet Tablet is designed for browsing and email functions, the phone maker said. The gizmo has a 4-inch horizontal touch screen with zoom and an on-screen keyboard. It can be connected to the Net either from a hot spot or using Bluetooth via a compatible mobile phone, Nokia said. The tablet runs on Linux-based Nokia Internet Tablet 2005 software edition, which includes desktop Linux and open-source technologies.