Sales of the Xbox One games console have more than doubled in the US since the cheaper Kinect-free bundle was introduced, Microsoft has claimed.

The machine, which was launched last November, originally came packaged with the Kinect motion-control device, at the price of $499. However, Sony's rival device, the PlayStation 4, arrived in the same month at just $399 with its own camera peripheral selling separately.

So far, the PS4 has reaped the rewards of being the cheaper machine, selling more than 7m units, with Xbox One lagging behind on around 5m. The $399 Kinect-free Xbox One bundle hit shelves on 9 June.

Microsoft originally stated that Kinect was an integral element of the Xbox One ecosystem. However, many consumers reacted against the idea of having a camera in their living room that seemed to be switched on by default, and able to record their movements and conversations. Furthermore, developers struggled to implement the device into their games, despite assurances that it was more accurate and powerful than its predecessor, the original Kinect on the Xbox 360.

In May, when Microsoft announced its decision to release a Kinect-free bundle, Yusuf Mehdi, corporate vice president for devices and studios, said the decision had been taken in consultation with publishers and development studios. Despite the success of the new bundle, executives maintain that Kinect is an important feature. Speaking to Tech Radar last month, Mehdi said, "I think Kinect is going to continue to be integral [...] We keep making improvements, perfections, and the progress on Kinect v2 has been pretty huge."

At the E3 games conference this year, the Kinect was barely mentioned during Microsoft's 90-minute press conference.

Equivalent sales figures from the UK and Europe have yet to be announced.

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