Convertible ultrabooks are no longer a new idea, and there are several takes on what ‘convertible’ actually means. On some devices, also known as ‘detachables’, the screen and keyboard separate completely, while others spot various 360-degree hinge mechanisms that allow the screen to lay flat against the keyboard, facing outwards in ‘tablet’ mode.

The new 13.3-inch Yoga 900 is an improvement on the Yoga 3 Pro convertible. The characteristic 360-degree ‘watchband’ hinge mechanism remains, so does the sleek, lightweight ultrabook design. The watchband hinge is smooth, reliable and flexible. It also clamps the lid and base sections firmly together in a feature Lenovo calls Auto Lock. Thin and light is the name of the game here, and at 1.49cm thick the Yoga 900 slips easily into a bag.

The Yoga 900’s desktop footprint of 32.4cm wide by 22.5cm deep is not unreasonable for a 13.3-inch laptop that requires a fair sized bezel to cater for tablet mode. The screen itself is wonderful. The 3,200-by-1,800 pixel IPS panel is bright and sharp with very vibrant colours.

Lenovo uses a metal-alloy fan, with cooling vents built into the hinge. These explains why the hinge feels slightly warm to the touch even when the Yoga 900 is idle. The warmth is not a problem, just an interesting approach to heat dissipation. Lenovo has boosted the battery capacity considerably from 44WHr in the Yoga 3 Pro, claiming up to 9 hours’ life from the Yoga 900’s 66WHr battery.