With a slim design and rounded edges, the iPAQ 314 Travel Companion (£246 inc. VAT) slips easily into the pocket. The 4.3-inch display has a resolution of 800 x 400 pixels, and offers a sharper picture than most of its rivals.

The N20 (£250 inc. VAT) is a mid-range sat-nav device from Navman. Although it comes with a reasonable price, it's far from stripped of features. At just 23mm in depth and with rounded edges, the N20 slips comfortably into small bags and coat pockets

Medion GoPal PNA470 review: Medion's GoPal PNA470 is the firm's new top-of-the-range satnav system. As you'd rightly expect from a GPS system that costs nearly £300, it comes preloaded with maps covering a huge geographical area

Budget electronic manufacturer Medion, a company that sells its products through supermarkets, is attempting to take on TomTom in the satellite navigation market. The Medion GoPal PNA460 (£199 inc. VAT) is a mid-range GPS device

ViaMichelin is a company that makes satellite navigation devices. Its X-970T (£247 inc. VAT) is a mid-range unit, and offers an excellent specification within a portable casing

Garmin's new nuvi GPS navigation device bills itself as a 'personal travel assistant'. Unlike other GPS devices, this machine isn't just designed to sit on your dashboard and coo "turn left" and "turn right"

The ViaMichelin X980T stands out from the pack, in part because of the enormous 4.3-inch screen, but mainly because it looks more like a cross between a Nintendo DS and a paperback book than a boring old PDA

Navman has built up a reputation as the manufacturer of intuitive satellite navigation devices offering unique features. Its S90i (£249 inc. VAT) continues this trend, and is both easy to use and packed with features.

Panasonic may be known for its household consumer electronics, but it also makes a range of satellite navigation devices. The Strada CN-GP50N (£299 inc. VAT) is a high-end product, offering all the features you’ll ever need.

Exclusive Binatone is a company traditionally known for its home phone products. After making a move into the satellite navigation market, the Carerra X430 (£160 inc. VAT) is its first product.

There are three members of the Acer p600 series that the company calls professional navigation devices. The p610 is the basic model at £180, the p630 costs £200 and adds European maps and Bluetooth, while this p660 is at the top of the tree

Sony may not be the first name you think of when it comes to satellite navigation, but its NV-U51G (£199 inc. VAT) is a legitimate rival to the likes of TomTom. It has maps of the UK and the Republic of Ireland pre-installed on 512MB of flash memory