Are they easy to use?
If you have only just turned the device on you may have to wait for it to find enough satellites to locate your present position. To set your destination, all you have to do is enter the post code, address with house number, street name or city centre. It then finds the destination based on the shortest or quickest route. If you go the wrong way or encounter traffic jams or detours on your journey it will work out another route for you.