Satellite navigation systems (Sat Nav’s) are the latest must-have gadget and are now an affordable mapping and routing solution for your journey planning. Using the Global Positioning System (GPS) your portable handheld or fixed satellite navigation system can determine your location (longitude, latitude, and altitude) to within a few metres using time signals transmitted along a line of sight by radio from satellites. Popular brands include TomTom, Magellan, Mio and ViaMichelin. Our reviews, advice and price comparison service will help you to choose the right satellite navigation system for you.