Sat nav reviews: Features explained
Sat navs give you automatic directions in a soothing voice. And, as you're driving along, you can easily check your location and journey progress on the sat nav screen.
Types of sat nav
There are three main types of sat nav devices - each with their own pros and cons.
| Sat navs - Integrated vs Dedicated vs Sat nav apps | |||
|---|---|---|---|
| Sat nav type |  Integrated sat navs (supplied with the car) |  Dedicated sat navs |  Apps (downloaded to a smartphone) |
| Pros | Factory quality installation Integrated into car sound system - excellent sound quality Large screen Sat nav display can often be linked to the dash display - easier viewing | Usable in any car Much cheaper to buy than integrated sat nav systems Easier and cheaper to update mapping | Usually cheaper than a dedicated sat nav - sometimes free Sat nav is always with you |
| Cons | Sat nav can only be used in one car Expensive (typically £1,000 + which you're unlikely to recoup when you sell) High potential for sat nav mapping to be out of date Mapping updates more expensive | Easy target for thieves Small screen Takes a little work to connect to car audio system, should you wish to do so. | Rarely outstanding sat nav performance - sometimes can be poor Need to buy a holder separately (although usually cheap) Need to buy an in-car charger (for long journeys) |
Sat nav screen options
Widescreen sat nav: easy to glance at
Screen size and widescreen sat navs
Sat nav screen size is defined as the diagonal measurement across the screen (in mm). Widescreen sat navs have a 16:9 aspect ratio, compared to the standard 4:3. Which? tests have found these widescreen sat nav systems generally offer clearer graphics and easier-to-read text.
They can also show two graphic images side by side in ‘split-screen’ mode, eg a detailed view of the roundabout you're approaching, next to a map view showing your overall direction.
Sat nav screen quality
The sat nav display needs to be big enough to view clearly. It should also be bright enough to be seen in daylight, and, preferably, feature anti-glare protection. Screen clarity has improved significantly with the introduction of widescreen sat nav systems.
Sat nav menus and advice
Sat nav menus follow the same convention as most modern computers and other electronic devices. Even so, some sat nav menus require more concentration than others to find what you’re looking for. This can create problems, for example, with some sat nav systems it's difficult to change routes mid-journey.
| Sat navs - Integrated vs Dedicated vs Sat nav apps | |||
|---|---|---|---|
| Sat nav type | Integrated sat navs (supplied with the car) | Dedicated sat navs | Apps (downloaded to a smartphone) |
| Pros | Factory quality installation Integrated into car sound system - excellent sound quality Large screen Sat nav display can often be linked to the dash display - easier viewing | Usable in any car Much cheaper to buy than integrated sat nav systems Easier and cheaper to update mapping | Usually cheaper than a dedicated sat nav - sometimes free Sat nav is always with you |
| Cons | Sat nav can only be used in one car Expensive (typically £1,000 + which you're unlikely to recoup when you sell) High potential for sat nav mapping to be out of date Mapping updates more expensive | Easy target for thieves Small screen Takes a little work to connect to car audio system, should you wish to do so. | Rarely outstanding sat nav performance - sometimes can be poor Need to buy a holder separately (although usually cheap) Need to buy an in-car charger (for long journeys) |
Map views – plan vs 3D
Whether you find a ‘top-down’ plan view or an ‘angled’ three-dimensional (3D) version easiest to read on your sat nav is a personal preference, so look at both to see which you like best.
Updating sat nav maps
The latest TomTom sat nav systems allow you to help correct mistakes in the maps supplied. The user can log problems on the move using the 'Mapshare' system, and next time the sat nav is connected to the internet (using a PC) this information will be uploaded to the TomTom database.
Once the correction is verified by TomTom it will be made available for all TomTom sat nav owners to download free of charge.
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Apple Macs
A quick word of warning: some sat nav systems can't be connected to an Apple Mac computer for updates. In this situation, ask for an updated map for your sat nav to be supplied on a memory card.
Setting up your sat nav
Sat nav installation
The most common fixing method for sat nav systems uses a windscreen sucker, but a few sat nav makers also offer a dashboard mount, which can be useful for cars with a steeply raked windscreen, as it means you can fix the sat nav closer to you.
Sat nav systems are usually powered or recharged by your car's cigarette lighter.
Sat nav set-up
To set up the sat nav itself, simply turn it on and follow the instructions to set up your preferences, such as whether you want imperial or metric guidance.
Next, tell the sat nav where you want to go; enter the address or postcode by selecting onscreen letters and numbers using buttons, a rolling wheel, or touch screen – and off you go.
Looking for points of interest on a Garmin 1695
Points of interest
Most sat navs offer points of interest. These are locations on your map that may be of interest – petrol stations, railway stations, restaurants and hospitals are some of the most common ones. You can search for your nearest restaurant, for example, and then ask the sat nav to take you there.
Many points of interest are pre-installed on your sat nav, although you can add new categories if you wish.
Some sat navs also have live services, such as Google local search. This enables you to search for virtually anything, from the nearest sushi restaurant to the nearest travel agency, live via Google.
IQ Routes and TrafficTrends
IQ Routes is TomTom's name for its technology that calculates the best route based on the time of day. It works on the idea that rush hour traffic flow is very different to 10pm on a Sunday night, for example. As well as a better route based on when exactly you are travelling, it also claims to calculate a more accurate estimated time of arrival.
TrafficTrends is a similar technology from Garmin.