Google has a good claim to the world's first fully-functioning wearable computer with Glass. Google Glass was made available to selected developers last year as part of a Google Glass Explorer Program. Google has recently released Glass 2.0  and opened up sales to the UK. Google is charging a heady £1,000 for Glass in the UK, a price which would make even the most ardent tech fanatic think twice.

Google Glass Explorer Edition 2.0 doubles the amount of RAM available on the original device, but there is no other hardware change. Google has also developed a companion app called MyGlass for Android and iPhone. Meanwhile developers have been busy creating a range of truly original apps for Google Glass. Google Glass is available in five different colours and the firm has introduced a range of frames for prescription lenses or to work as sunglasses (the frames cost £120 but a pair is included in the price, don’t forget to add it when you checkout). These frames open up Glass to those who need prescription glasses, but they may also help normalise what is effectively a head-mounted computer.

Google Glass is a unique device; there isn't much to compare it to on the technology market. You wear Glass as you would a pair of glasses, but it features an optical heads-up display that projects a display in front of your eyes. Interaction is by means of voice commands, accelerometer and gyroscope and a thin strip known as the “Touchpad” that runs alongside the right hand side of the frame. 

Glass shares some of its design DNA with smartphones: you can check email, post to social media, take photos and videos, search Google and download apps. But it is a radically different experience and is designed to sit alongside your smartphone, rather than replace it.

Next section: using Glass, in the UK on a regular basis