Love them or hate them, GPS devices are rapidly becoming more popular for all kinds of outdoor pursuits. They can be used for checking your position, following a pre-defined route and automatically recording your route. Some offer additional features, such as cameras or altimeters. Here’s the Ordnance Survey guide to choosing a handheld GPS device.
What do you need it for?
The first thing to decide is what you need to use the device for. You get GPS devices for cars, motorbikes, bicycles, and on foot. Each of these is an area in their own right, so I’ll be concentrating on handheld GPS units designed for waking, geocaching, orienteering and other outdoor activities.
If you just need to confirm your position in latitude/longitude in an emergency or as a backup for traditional map and compass navigation, you probably only need one of the simpler GPS devices. The smallest GPS devices are the watch size ones, but these are targeted mainly at the sports market, and are designed to record speed and distance, but generally do not give your location, and do not have any on screen mapping.
If you are looking to partly replace a paper map, you will need a device that shows maps on-screen, preferably with a reasonable screen size and maps covering the right area in the best scale.
Dedicated GPS, Smartphone or Tablet?
Most makes of smartphone and tablet come a choices of mapping, from simple apps that just show the position to full on screen mapping. If you already own a phone or tablet, these can be a cheap way to get a GPS device, with the bonus of not having to carry an additional piece of equipment. They generally sport cameras, compasses and other add-ons that can make them an attractive option.
However, most of the apps do not work when there is no mobile signal, or have reduced functionality. As many of the places you are likely to be using GPS navigation have poor mobile coverage, you need to ensure the app downloads all the maps you need to the devices local memory. Some mapping apps offer caching, where the map can be opened where you have a data connection and is then stored temporarily on the device, but these can be unreliable if you move off the edge of the cached area, or even restart the app.
To avoid this, look for apps which allow you to download maps to the device memory, such as our own OS MapFinder.
One other drawback with smartphones or tablets is that few are designed to be weatherproof. The simplest solution is keeping them in a waterproof pouch, ensuring you can still see the screen and operate the controls. You may also want to consider adding a case or other protection from knocks or drops.
Lastly, check the battery life of your device. If you are relying on a GPS as your main navigation method, most tablets or smartphones (unlike dedicated GPS units) do not have easily replaceable batteries. Bring a spare battery, an external battery booster or some other means of recharging if you are going to be using any GPS device. If you use a smartphone, be aware that it is also your emergency call device, so you do not want to be stranded with no GPS and no phone when the power dies, or it gets damaged. Think about carrying a spare, fully charged phone for emergencies.
It’s all about the maps
When choosing your GPS device, pay attention to the maps included and available as extras. Most GPS devices and apps come with a basemap, but these are often at road mapping scales, and not really suitable for walking or off-road uses. For the UK, Ordnance Survey maps are available as options from most of the main brands of dedicated GPS. These have the advantage of matching your paper map exactly simplifying your route planning.
When you are buying a new GPS unit, look at the bundled maps on offer. You will often find that you can save a lot of money by buying them at the same time instead or purchasing them later. Generally, maps bought for different GPS brands or different apps are not transferable to another brand of device, so ensure you are happy with the functions before buying add-on maps.
Some of the dedicated GPS units come with external software, such as Garmin’s Basecamp or Memory-Maps’ PC version. This makes it easier to transfer maps and routes from a PC to one or more GPS units.
Even with full mapping on an electronic device, we always recommend taking a paper map (and compass) as a backup. You never know when a device might fail, get lost or damaged. If you are forced to stay out longer that expected that is exactly when you most need a reliable map – and when the batteries are most likely to give out.
What Functions do you want of a GPS Device?
GPS Position: All GPS devices do this, but some only report latitude/longitude while others will report also OS grid reference, altitude and distances to the next waypoint. Generally, more expensive GPS units will give more accurate results in less ideal situations, such as under trees, in ravines or near buildings. This is not something you can usually test yourself, so you may have to rely on reviews or recommendations.
On screen mapping: If you have a device that shows a map on screen, check it is available in the correct scale. Check how well the screen performs under different light conditions, from direct sunlight to low light or torchlight. Brighter screens are more usable, but often at the cost of shorter battery life. Also check the display resolution, as high resolutions will show more detail on the map.
Batteries: Bigger screens and more features tend to use more power, either shortening batter life or adding to the weight. Check the expected batter life meets your needs, whether you are a day walker or a multi-day hiker. Replaceable batteries in standard sizes are a big advantage for longer trips, as it’s easier and cheaper than proprietary battery packs or recharge kits.
Waterproofing and durability: Dedicated GPS units are generally designed to cope with rain, while some can handle full submersion. If the device does not have one included, a rugged case can make it easier to hold and more drop resistant.
Buttons and touch screen: Some devices now use touch screens, and while these can make it more intuitive to use they are also harder to use with cold hands or when wearing gloves. Most touch screens on dedicated GPS devices are designed to work while wearing thin gloves, but thicker gloves will make accuracy difficult.
Magnetic compass: Some GPS units have an included magnetic compass, which allows you to check the direction you are facing easily. Without a magnetic compass you will have to move a short distance to the GPS device can calculate the direction you are moving.
Memory: Maps can take a lot of storage space, so ensure the memory is sufficient for the maps you are going to be using. Some devices use external memory cards, while some have only internal memory, while others have a combination of the two. External memory cards do have the advantage of being easily interchangeable, while internal memory usually requires a data connection.
Connectivity and software: Check what connections your device has – the most common in USB which makes it easy to connect to any modern computer. Many of the dedicated GPS devices come with software for adding maps, and may also include route planning abilities.
GPX files are one of the standard formats for importing and exporting GPS routes. They consist of a series of points, and being able to import and export GPX files will allows you to import and export routes to other programs, such as OS getamap and OS MapFinder. This is a really useful function for sharing routes, or downloading new routes to discover. If you want to be able to do this, check that either the GPS device itself or the accompanying software is capable of handling GPX files.
Barometric altimeter: GPS is not very accurate for calculating the altitude, so if you want a higher accuracy look for a device with a barometric altimeter. This uses the air pressure to give a more accurate reading for altitude.
Built in camera: Record your travels with a built in camera. Having one in the GPS saves carrying a separate camera, and photos will generally be tagged with their exact location, which can be really useful for building a trip scrapbook later. The higher the MP (megapixels) of the camera, the more detailed the image will be, but you will generally find a dedicated camera will have more options and create better photos, especially in more difficult conditions, such as poor light or reflective snow.
Route Recording: Being able to record your route allows you to review it and share it later. It’s great for settling arguments about how far you have travelled (and the vertical difference). If your device has GPX export you can then send this to others as a file, allowing them to follow your route more easily.
Waypoints and routes: Being able to store multiple routes on the device gives more flexibility, especially for longer trips. You will also be limited by the maximum number of ‘waypoints’, showing the next destination. Higher is better, but if you only plan to go on day trips a handful of routes and a few hundred waypoints are sufficient, while those on multi-day trips will need more storage. Some downloaded routes can have a lot of waypoints, and recording a route can create a lot of waypoint data as well, so having more space ensure you do not lose the end of the route. Some devices store imported routes and recorded routes separately, so you may have two different numbers.
Note that different manufacturers do not use the same terms for routes, especially the difference between recorded routes and created/imported routes, so when looking at storage make sure you understand the difference.
Accessories: Depending on your needs you might want to add some accessories, so check what is available for your device. Some of the accessories include:
- Chargers for car power sockets
- Car, bike or motorbike mounting kits
- Heart rate monitors
- Storage and rugged carry cases
- Belt clips
New GPS devices and apps for smartphones or tablets are coming out all the time and will undoubtedly add new features, but as long as a GPS device is suitable for your personal needs you may not always need all the latest options. For a range of GPS devices from the top manufacturers, check our GPS Devices section in the shop.