Buyer's Guide: The Best Sat Navs

Web-connected services are making sat navs more feature-rich and more intelligent than ever, with improved traffic information and points of interest, in particular. While a smartphone navigation app can be handy for occasional use or for shorter journeys, budget sat navs are as competitively priced as ever these days. Here are a few things to look out for when shopping for a sat nav:

- Screen. A bigger screen makes a sat nav more comfortable to use, especially when it's mounted quite far away from the driver. We're starting to see models with 5-inch screens, but 4.3-inch displays are still the norm. However, unlike a smartphone, you can't slip a large-screen GPS into your pocket.

- Text-to-speech. With this function, the GPS will read out loud the names of streets and roads you need to follow. Only a few entry-level models don't have this feature nowadays. Text-to-speech shouldn't be confused with the less advanced vocal instructions found in all sat navs, like 'turn left' or 'take the second exit at the next roundabout'. A GPS with a text-to-speech function will be able to say 'turn right onto Station Road', for example.

- Traffic info. A real plus point for connected GPS units, real-time traffic info services are becoming ever-more accurate. We found TomTom's HD Traffic service to be the most reliable, but other manufacturers' services are gaining ground. Otherwise, the more basic TMC-RDS traffic info service uses signals broadcast by FM radio stations to receive information about the current state of the roads. This service isn't as accurate, however.

- Advanced location search. Some sat navs use Google, the Yellow Pages and even travel guides to help find locations without you even having to enter the address!

- Intelligent route calculation. In TomTom and Mio sat navs, IQ Routes technology uses actual road-speed data to calculate the most efficient routes. Routes are therefore adapted to reflect real driving conditions rather than being based on theoretical speed limits. Navigon and Mio sat navs offer a choice of routes so you can pick the most appropriate.

- Maps. Most sat navs come with maps of Europe these days, although you can still pick up budget options with UK and ROI maps only. You usually have to pay for map updates but Garmin offers unlimited updates for life as an option with some of its GPS units.

- Bluetooth and voice recognition. With Bluetooth, you can use the GPS as a hands-free kit by connecting it to a compatible mobile phone. Voice recognition functions aren't anything to write home about just yet, as while they're pretty effective for basic commands, they can struggle to understand addresses.

With these factors in mind, here's our pick of the best sat navs out there right now.

Editor's Choice

The TomTom GO LIVE 820 and 825 are almost identical to the Via LIVE 120 and 125 they're designed to replace. However, their design has changed a fair bit and they now have a handy Micro SD memory card slot.

TomTom's LIVE services (1 year free then £50 per year) include HD Traffic to help you stay one step ahead of traffic jams and avoid congestion. Services also include mobile speed camera information, Google local search and weather reports.

On top of that, you'll find TomTom favourites like IQ Routes for intelligent route calculation using road-speed data and Map Share for map updates from the user community. There are loads of points of interest to keep you entertained, plus text-to-speech and voice recognition functions, not to mention Bluetooth. All in all, this is one of the best sat navs on the market.

Two Alternatives

Best of the Rest

Here are a few more of our favourites.