Asus Eee Pad Transformer Prime

The Eee Pad Transformer Prime is Asus's latest Android tablet computer. Unlike many other tablets which are dependent on touchscreen keyboards, it comes with a detachable physical keyboard so it can be used like a laptop if you wish.

The Prime is light for a 10in tablet at just over 600g and it's not much thicker than a couple issues of Computeractive. Despite its thinness, it feels sturdy yet sleek thanks to its lovely metal construction. Asus has managed to squeeze in micro SD card slot so you can add more storage if the built-in 32GB isn't enough. There's even a HDMI port for connecting the tablet to a TV.

Plugging the Prime into its accompanying keyboard increases the weight to 1.2kg, but it still feels light and robust. The tablet is held securely in place - to release it, just slide the release latch. The weight of the keyboard is uneven though, so it feels like it might tip over and it's difficult to balance on one's lap. It's also far too easy to accidentally brush against the touchpad when typing and causing all sorts of mishaps, although the touchpad can be turned off using a button.

The keys themselves feel shallow and some keys are narrower than the others, so typing on it isn't quite as accurate as it is on a full-size laptop. Still, typing on it is much easier and faster than typing on any touchscreen keyboard. Android doesn't support all the keyboard shortcuts we'd expect from using a PC. This means you'll often have to switch between the touchpad, touchscreen and keyboard which isn't comfortable.

The keyboard does have other benefits though. It has a full-size USB2 port and SD card slot for copying files to and from USB memory keys and SD digital camera memory cards respectively. Best of all, the keyboard has a second battery. When using the Prime to play videos, this extended the battery life from an already impressive nine hours and 43 minutes to 18 hours and 30 minutes.

We were dazzled by the incredibly bright 10.1in screen, which has a high resolution of 1,280x800 pixels so it can show lots of detail. Brightness can be boosted even further to make the screen visible outside in bright sunlight, but this is best used sparingly as it saps battery life.

The new Android 4 Ice Cream Sandwich operating system isn't that different from the previous 3 version, but it does feel noticeably smoother and more responsive than its predecessor. This is at least partially due to the Prime's powerful new quad-core processor. Few apps take advantage of it, but the few that do, mostly games, look impressive. Cleverly, the processor also has a more energy frugal fifth core for simpler tasks, such as writing emails, to conserve battery life.