At Mobile World Congress (MWC) on Monday, Telefonica showed off a prototype phone using B2G (Boot to Gecko), Mozilla's browser-based OS. It can't match today's higher-end smartphones, but it'll be good enough to sell by year's end, Mozilla says.

Telefonica showed off B2G, the Mozilla browser-based operating system for mobile phones, saying that it's good enough to sell to today's feature-phone customers later this year. You may or may not agree. To help you judge, we've got a video below of Carlos Domingo, Telefonica Digital's director of product development and innovation, demonstrating a prototype phone at a press conference today at the MWC show here. At the event, Telefonica announced its mobile OS pact with Mozilla. Having watched the demo myself, the phone looked workable, but awfully pokey. And touch input — especially the keyboard — was evidently a challenge. These are early days for B2G (which stands for Boot to Gecko), but, in the meantime, iOS and Android show no signs of slowing down, and Windows Phone is gaining adherents.

Top-end performance isn't everything, though. Telefonica's B2G-based phone will cost one 10th of what an iPhone costs, Domingo said in an interview. Mozilla argues that because the web engine runs directly on Linux, without the intermediate software layers used in iOS and Android, it can use lower-end hardware. The demonstration used a Qualcomm-built reference design with a 480x320-pixel screen. Domingo used it to put a call through to another phone, sent and received text messages, won a score of 317 at the HTML5 test website, played two lightweight games, and read a Frankenstein ebook. Mozilla Chief Technology Officer Brendan Eich didn't pretend that the phone's up to the challenge of 3D graphics. But he did say that the phone is advancing rapidly. The B2G operating system, which combines Mozilla's Gecko browser engine with a Linux kernel hidden underneath, runs web apps, not native apps, which means that they use web standards such as JavaScript, HTML, CSS and webGL. That's good for many games and sites with web-based interfaces today, but it'll take some convincing for other programmers. And iOS and Android have a lot of programmers on-board already.