Firefox OS smarthpones Keon and Peak

Smartphones running Mozilla's Firefox OS have gone on sale today.

Spanish retailer Geeksphone has put two Firefox OS smartphones up for sale today. Developers and early adopters can now get their hands on the Keon and Peak handsets with price tags of €91 and €149 excluding VAT respectively. See also: Firefox OS on ZTE Open hands-on review.

With another mobile operating system to take on iOS, AndroidWindows Phone 8 and BlackBerry, Geeksphone has been overwhelmed with demand. Unlike its rivals, Firefox OS is a web-based operating system which runs HTML5 apps.

Geeksphone said: "Wow initial previsions were largely surpassed! Devices will be back on stock in a few hours, thanks for your support!"

At the time of writing, the online shop is unavailable. The firm has not announced how many units it has available so it's unclear just how much demand there has been for the Firefox handset.

The developer preview devices were announced in January and the Firefox OS was shown off at this year's Mobile World Congress show in Barcelona. Take a look at our video demo of the operating system running on the ZTE Open below.

The Keon features a 1GHz Qualcomm Snapdragon S1 processor, 3.5in (320 x 480) screen, 4GB of storage and a 3Mp camera. Meanwhile, the Peak uses a 1.2GHz Qualcomm Snapdragon S4 dual-core processor, 4.3in qHD IPS screen, 4GB of internal storage and an 8Mp camera.

"Our developer preview devices have been designed to enlighten the Firefox OS experience, giving developers the chance to tap the future of mobile." said Geeksphone.

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