Asus Zenbook UX21

The Asus Zenbook UX21 is an ultrabook - Intel's term for thin and light laptops with long battery life and the ability to wake from sleep very quickly. The Zenbook is very light at 1.1kg and it's just 3mm thick at its thinnest point, so it should be easy to carry around. It still feels sturdy and well-made though thanks to its rigid metal design. It looks very attractive, but also looks strikingly similar to the Apple MacBook Air.

Asus claims a battery life of fives hours for the Zenbook and our tests showed that the battery, which is not designed to be replaced by the user, exceeded this lasting just under six hours when browsing the web. It also wakes from sleep almost instantly, unlike other laptops which can take several dozen seconds to do so. This is no doubt due, at least in part, to the solid state disk (SSD). This is faster and more durable than a standard hard disk, but the downside is the amount of storage available. The SSD is just 128GB in size, so if you have lots of files then you may have to pick and choose which ones you want to carry around with you.

The Zenbook isn't powerful enough to play the latest games, but it's quick enough for other tasks since it has a 1.6GHz Intel Core i5 2467M processor and 4GB of RAM. Adding more RAM isn't possible, but 4GB should be enough for running the software most home users will want.

As with other ultrabooks there's no built-in DVD writer. The thin design also means that there's no Ethernet port or memory card reader built-in, but an Ethernet adapter that plugs into one of the two USB ports is included. One of the USB ports supports the very fast USB3 standard - this will be useful for connecting very fast storage devices such as hard disks and flash drives.

Although the Zenbook is available with a 13.3in screen that has a high resolution of 1,600x900 pixels, the model we reviewed had an 11.6in screen and a resolution of 1,366x768 pixels so it can't show as much detail onscreen. It's bright, but the small size of the screen may not be comfortable viewing for everyone. If you want to connect another monitor, there are HDMI and VGA ports for doing so, but these are smaller-than-usual 'micro' versions so you will need adapters - only a micro VGA adapter is included in the box.

The Zenbook's main weaknesses are the keyboard and touchpad. The keys aren't too small, but they don't give enough feedback when pressed. This makes it difficult to type on without making frequent errors. Unlike some other laptops, the keys aren't backlit for working in the dark.

The touchpad is large, but moving the pointer doesn't feel very accurate. Another annoyance is the buttons. Instead of being separate from the touchpad, they are built into the corners of the touchpad itself so a firm press in a very small area is required, which is fiddly and not very comfortable.

The Asus Zenbook would be a great laptop for use while travelling due to its good battery life and low weight, but its poorly designed touchpad and keyboard make it frustrating to use. It's not a bad laptop, but better buys are available.