In February, we got our first look at Mozilla's Firefox OS, a smartphone operating system built on the open web. On the first two phones, the ZTE Open and Alcatel One Touch, it was a laggy, terrible experience. We'd hoped that Mozilla would improve that by launch, but apparently not: though the ZTE Open will go on sale in Spain tomorrow, we found the phone as unimpressive as ever at today's Mozilla event.

Brendan Eich, co-founder and CTO of Mozilla Corporation, made it clear that Firefox OS isn't going to compete with today's top-tier smartphones. "We are not aiming high and trying to crash into Fortress Apple, into Fortress Google," he said at a San Francisco briefing today. Instead, the company's going after the feature phone market, hoping to entice all those potential buyers who've stuck with dumber, cheaper devices up till now. So far, Apple's interest in that space has been limited to selling older models, though there are rumors that it might release a low-cost iPhone in the future. But what's to keep Fortress Google from nipping Firefox OS in the bud with a wave of cheaper devices?

Eich's argument that Firefox OS could make a dent in the low-end market is that the Android operating system is simply too bloated to run on cheap hardware. In order to build a truly mass-market smartphone, he explains, you need to reduce the amount of memory you use, and select low-end processors (say, a single-core CPU) that silicon vendors can sell much more cheaply because of the binning process. "If you don't balance the physics out, the semiconductor makers lose money," Eich says.

Of course, Mozilla thinks that Firefox OS has Android beat when it comes to a lightweight smartphone operating system. An Android handset's processor, Eich says, has "three mouths to feed" in that it has to power three separate pieces of software: the Android kernel, Dalvik, and WebKit. By comparison, hardware running Mozilla's Firefox OS only has to power the Gecko web browser rendering engine.

But we've already seen how well Gecko works on cheap commodity hardware, in a $90 phone going on sale tomorrow. It's just not very good. Firefox OS feels just as slow and laggy on these mobile devices as Android does without enough processing power — if not more so.

And what happens after the semiconductor industry has advanced such that dual-core processors and 1GB of memory are the new point of entry, thanks to Moore's Law? "In the future we'll all have Google Balloons and terahertz processors, and life will be great," says Eich, dismissively. Right now Mozilla has a chance to fill a hole in the market, he believes, and if the idea of open web apps catch on, Firefox OS will have been there from the start. "[Google] turned a blind eye to it too soon, and timing is everything," says Eich.

Certainly, Mozilla has quite a few cellular carriers on board, and a pretty clever strategy that could guarantee phones on shelves. But is there ever a right time to ship devices that don't run particularly well?

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