Magellan's Maestro 3100 is an extremely small satellite-navigation device, which makes it a good choice for anyone who wants to stick it in a pocket after taking it out of the car.

However, one downside of being so small is that the screen is relatively wee too, and although it is clear and bright, the size makes map reading a little tricky.

It's a touch-screen device, which means that people with bigger fingers might find that they are continually touching the wrong commands, as the icons are not only smaller but are also placed very closely together, to fit into the screen's size.

The 3100 comes preloaded with UK maps, which can be viewed in 2D or 3D and with night or day colours (the night setting is a high-contrast mode for seeing in the dark).

When we first set up the device it took a good few minutes to find the destination. That's something we put down to the fact that it was the first time it had to calculate a route, but it continued to be very slow for every other route calculation we tried.

Once the 3100 picks out the route, there are several ways to see it. The Show Map feature brings up a basic overview map pinpointing your current location, as on a map website. For those who want something more precise, selecting Enter Address and putting in a postcode, address or point of interest will instruct the 3100 to plan the route to that point. The Trip Planner feature is good for those wishing to plan a journey with more than one stop.

We found both the latter options very precise and easy to use. The device calculates routes based on either time or distance, and there's a detour option to instruct it to avoid motorways or sheep-filled country roads.

The voice navigation on the Magellan 3100 is extremely clear, and the supplied voice is friendly enough. That said, like a friend, and like many satellite navigators, it sometimes completely failed to give the instruction to turn until the very last second.

The best thing about the 3100 is its split-screen mode, in which one side of the screen continues to show the route, while the other shows the next turning to take, before you have to make it. This was particularly helpful when driving along a spilt section of motorway, for instance. In all, though, the split-screen doesn't quite make up for the poor interface and slow start times.

Vista compatible: N/A