Not specified

The starter pack contains (contained) six cubes, a charging dock and AC adapter, a USB dongle, two free games, 500 points to spend on other titles and can be yours for £230 (ext VAT).

https://www.ebay.com/p/Sifteo-Cubes-Intelligent-Play-Interactive-Game-System-Age-7/1601507880 $ 59.99

It seems that they have stopped producing Sifteo robots and have shut things down a few years ago.

This announcement is on the facebook site: “We’re excited to announce that we have joined 3D Robotics! Thank you, everyone, who has been a part of the Sifteo journey. http://farewell.sifteo.com/”  24.07.2014

https://www.teachprimary.com/tried_and_tested/view/sifteo-cubes

Sifteo Cubes are a hands-on interactive game system. You can turn cubes, shake them, press down on them, and connect them with each other. Each cube contains a tiny computer chip and is connected to other cubes, sensing their motion and position through a wireless network to the Sifteo application on a nearby computer.

You can use the cubes to bring characters to life in a storytelling game, crack codes, match shapes, find your way through mazes, see addition and subtraction in action, unscramble pictures, test your reflexes, practise your spelling and much more. You can even code and create your own games using Sifteo’s innovative Creativity Kit.

Sifteo comes with desktop software that allows you to browse and play games, create your own with the Sifteo Creativity Kit, and find more in the Sifteo store.

There is a software developers kit but it requires that you know the programming language C. There is also a Creativity Kit which does allow you to change some of what you might call the “vocabulary” of the games (the letters and words) but only allows limited changes to the grammar – the underlying structure – of the games.