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device that determines its position by analyzing GPS satellite signals
(Redirected from Satellite navigation)
Travel topics > Transportation > GPS navigation

Satellite navigators, such as GPS devices, use satellites to get your position. They can often be equipped with maps and be told your intended route or calculate routes to your destination. We use the term "GPS" here, although some devices use other satellites, often in addition to GPS ones.

Understand

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A world of technology

If you're shopping for a GPS device for specialized uses, it may help to be familiar with some of the acronyms and technologies.

  • GNSS (global navigation satellite system) — A general term that includes all of the current navigation systems: the U.S.'s GPS, Russia's GLONASS, China's BeiDou (BDS), and the EU's Galileo.
  • A-GPS (Assisted GPS) — Using cellular networks or internet connectivity to help determine its position faster or more accurately.
  • WAAS (Wide Area Augmentation System) or SBAS (satellite-based augmentation system) — These broadcast data to improve accuracy over a large region, typically covering most of a country or continent, by accounting for factors like atmospheric conditions. This typically improves accuracy from 5–15 m (16–49 ft) to around 1–3 m (3–10 ft). Since these use the same radio spectrum as the positioning satellites, it's easy for manufacturers to add and has become fairly standard.

    Such systems include the U.S.'s WAAS, Russia's SDCM, the EU's EGNOS, Japan's MSAS and QZSS, and India's GAGAN.

  • LAAS (Local-Area Augmentation System), GBAS (ground-based augmentation system), and DGPS (Differential GPS) — These broadcast data to improve accuracy for small regions. They are mainly used for airports and marine harbors, and improve accuracy to less than 1 m (3 ft) and as little as 10 cm (4 in).
  • Dead reckoning — Estimating position when the signal is lost, such as when driving through a tunnel. A simple implementation might just assume the speed you're travelling remains constant; more advanced devices might use accelerometers or the car's speedometer and steering wheel position to make a more accurate guess.
  • WGS84 — the coordinate system used by GPS.

Although most people are familiar with using GPS navigation while in their home area, GPS navigation can easily become your most useful tool when traveling or Wilderness backpacking. They can give you live directions while driving, hitchhiking, cycling, hiking, walking or catching public transport. They can help you stay on the well beaten path. But better still, they can tell you where you are, allowing you to get hopelessly lost in the medina of Marrakesh, and then allow you to wander out when you feel like it. Or tell you the name of the small church you are cycling past on the Rallarvegen. Or for those who like every second of their day planned, you can load up your daily sightseeing route, and make sure you keep to your schedule. They can give you confidence to explore!

These days, practically every smartphone (and even some feature phones) offer GPS. Many cars also offer a trim package that includes built-in navigation, and via Android Auto or Apple CarPlay newer ones can often display your phone's navigation apps on their screen. You can also use stand-alone devices designed for a variety of specific uses such as driving, hiking, or boating.

GPS devices with cellular or internet connectivity can determine their position in as little as a few seconds of being turned on, using nearby cell towers or Wi-Fi networks to obtain a rough position and download data about the satellite network. But standalone devices must download all the required data from the satellites; if it's been more than a few hours since the device was last used, this can take up to 30 seconds (or potentially much longer if conditions are poor, such as not having good view of the sky or moving rapidly).

GPS uses the coordinate system WGS84. There are other systems in use. ETRS89, used in much of Europe, follows the European continental plates instead of global averages; it is still close enough for navigation purposes (the difference is less than a metre). In some countries, one needs to be especially careful, e.g. the coordinates used on Chinese maps differ significantly from WGS84. Also, sometimes Cartesian coordinates are used instead of the angle-based ones of the GPS. If you need to communicate your coordinates to other people, make sure they understand that you are telling the coordinates from the GPS. Also, when using a paper map, make sure you know how to use the GPS to position yourself on that.

Smartphone apps

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A GPS for use in a car

Using GPS navigation apps on your smartphone can be the easiest and most convenient way to navigate when out of your home country. It can save money over buying a standalone GPS device and new maps for it, or renting one from a car rental company. Several smartphone apps are able to give an approximate location using known locations of Wi-Fi signals when they cannot get satellite data. However, if you don't have a data connection for your phone, or when it is out of range, their performance can be limited or their maps unavailable. If your app can't give you directions, that's usually what's wrong. For use in challenging conditions, a dedicated GPS device with physical buttons may still be a better choice than the touch screen of a smartphone.

Some apps allow download of maps before departure or while on Wi-Fi, avoiding the need to have a live data connection or to consume data on mobile telephone networks while moving. However, you need to have enough storage capacity in your phone. On the other hand, if you have a weak and useless Wi-Fi connection, you may want to turn it off or move further away, and start using cellular data.

Most of the apps mentioned here cannot be used in mainland China and South Korea, due to national security laws requiring navigation to be provided only by local apps. In China, the most common navigation apps are Baidu Maps and Amap, while South Korea uses Naver Map and Kakao Map. In addition, while Western GPS navigation apps are not banned in Russia, they may not be up to date due to Western sanctions on Russia. Instead, Russians use Yandex Maps for their navigation needs. The restrictions for mainland China do not apply to the Special Administrative Regions of Hong Kong and Macau, so the usual Western navigation apps can be used in the two territories.

Some devices and apps make use of systems other than the U.S.-operated GPS: China's BeiDou, Russia's GLONASS, and the EU's Galileo. The differences should not affect a casual user's experience.

OsmAnd

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OsmAnd navigation options.

An open source app for (offline) maps and navigation by OpenStreetMap (OSM). OsmAnd focuses on car, bicycle, and foot navigation via GPS (and others if available to the phone). There is also some support for public transit, nautical, and ski navigation.

While the car navigation of OsmAnd can barely compete with Google Maps (and lacks traffic information), it out-competes the competition by far on the non-car navigation side. The level of detail provided of course depends on OpenStreetMap coverage, but for tracks and trails it remains unrivaled in most parts of the world. Offline functionality, GPX import and export, as well as the optional use of elevation information are particularly handy for hiking and biking trips. It is also one of the few foreign apps that work reasonably well in mainland China.

The easiest way to install OsmAnd is by using Google Play or the iOS App Store. This might not be the best choice, though, depending on what functionality you require and whether you are willing to pay. The basic version of OsmAnd that is available free of charge is limited to 7 in-app map downloads — after that, new maps and updates need to be downloaded manually. The paid version OsmAnd+ can download unlimited maps and updates. Users of Android phones can also get the fully featured and free-of-charge OsmAnd~ from the alternative F-Droid app store. Active OpenSteetMap mappers and editors logged in through the OpenStreetMap editing plugin can also receive unlimited map downloads even on the basic version. Finally, as OsmAnd is free/libre open source software, technically savvy users can even build the full version of the app from source.

Map downloads and updates matter, because the main purpose of this app is to work without access to the Internet. All maps are stored locally on your device, but that also means that they have to be downloaded before using the app. Be aware that some countries or regions have maps which are quite large, like 1GB and more. And hillshades and elevation line maps require another bulk amount of space on your phone. So, don't just start downloading maps randomly, but check which ones you actually need.

Maps are generally updated monthly. Hence, there is an additional subscription service called OsmAnd live, that offers hourly map updates for a monthly fee—50% of which is used to support mappers working on OpenStreetMap.

Here some more notable features (besides navigation and many others):

  • Trip and trail recording (GPX), including upload to Openstreetmap
  • Route planning, route export and/or route import (GPX)
  • Display of velocity, elevation (profile), and distance
  • Definition or selection of arbitrary overlay/underlay maps (Bing Earth, Yandex Satellite, Openstreetmap Traces, Google Maps Traffic, Google Maps, various Cycle Maps, and even self-made SQLite maps)
  • Choice of emphasis on: Offroad, touring, bus/tram/subway/train routes, hiking trails, MTB/cycling routes, ski slopes, horse treks
  • On-the-fly Openstreetmap editing of POIs (bulk or single upload later)
  • Parking position recording
  • Street level photos via the Mapillary service
  • Hillshades and elevation lines display (OsmAnd+/~ only)
  • Articles from Wikipedia pages related to POIs (those with GPS location) for offline reading (OsmAnd+/~ only)
  • Offline copy of Wikivoyage and integration of POIs/listings into the map (OsmAnd+/~ only)

Other OpenStreetMap based apps

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  • Mapy.cz – Another popular app and similar to OsmAnd, but not open source. It has been around for almost the same amount of time and found an equally enthusiastic base of users and supporters.
In case OsmAnd does not cover your needs or is too challenging, try this app. They also have Android and iOS version: Mapy.cz
  • Organic Maps – A newcomer as of 2023, created by the original developer team of Maps.Me. Functionality and map details are limited, but it is an easy app to navigate with based on OpenStreetMap information.
Supports GPS, navigation by car and on foot, and limited OpenStreetMap editing. But in remote regions and outdoor action, this app should probably not be leveraged.
  • Maps.Me – Not maintained actively anymore, but still working. And since the downloadable maps originate from OpenStreetMap, the non-maintenance should not pose a problem for the reliability of the app.

Google Maps

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Google Maps is the global behemoth of proprietary maps applications. It has maps of just about everywhere you would like to drive and where people regularly go, provides turn-by-turn directions, and allows you to download offline maps for areas in advance. It continues along a planned route even when it loses data signal. When the application is offline, the search results of places and turn-by-turn navigation are limited. The more information you give it before leaving (with a Wi-Fi connection) the better. If you have a basic smartphone, or are running out of storage, you can use the Android app Google Maps Go. This runs online on the Chrome web browser and creates an icon. A second app is needed for navigation: Navigation for Google Maps Go, and the latter does not create an icon.

Google Maps fails to convince when it comes to anything other than navigation in populated areas or by car or searching for nearby POIs (which covers "most" scenarios for its typical users). Its coverage of hiking trails is poor, and even in populated areas its transit and walking directions are a mixed bag. Beware: Never rely on Google Maps for remote and offline navigation purposes—people have already attempted to reach canyons and summits with Google Maps telling them to follow a straight line right to their destination. This is highly dangerous in unknown and remote places and should never be attempted!

Waze

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Waze is available on the Google Play and iOS App Store. It's the world's largest crowdsource navigation system, and completely free (ad-supported during stops). While it is a bit weaker in data relating to traffic congestion and accurate maps than Google, Waze is well known for giving warnings for road hazards and police activity. It also gives updated fuel prices for gasoline/petrol and diesel. Interestingly, Waze is owned by Google, but kept as a separate operation. However, Waze map editors can now use Google's satellite maps for better accuracy. Waze maps tend to emphasize the road itself, rather than the periphery. Not recommended for offline use while driving, though brief "dead spots" aren't usually a problem. Initial Wi-Fi route setup can eliminate much of cellular data usage.

Apple Maps

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Apple's proprietary mapping solution comes pre-installed on every Apple device with a screen. Widely panned by users for its inaccurate data when released in 2012, several updates have since improved its accuracy, and the service now matches Google's quality in many regions of the developed world.

Downloadable offline maps are available as of iOS 17.

CoPilot GPS

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One country map can be downloaded for free and used with restricted functions. Additional maps can be purchased after an upgrade to voice turn by turn navigation for US$24.99.

Brazil, Australia, New Zealand, US, Canada, UK, Ireland, Balkans, BeNeLux, Russia, Central Eastern Europe, DACH, France, Greece, Iberia, Italy, Nordics, Poland, Romania, Turkey, Ukraine, South Africa, Lesotho, Swaziland, Namibia and Botswana. Middle East Maps (Bahrain, Jordan, Kuwait, Lebanon, Oman, Qatar, Saudi Arabia, UAE).

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Application with maps from OSM. For iPhone only, with limited country support. Basic maps are free (ad-supported), with in-app purchases for turn-by-turn navigation and other features.

Standalone GPS navigators

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Some still choose a standalone navigation device, rather than using a smartphone app. There are several reasons why a smartphone may not be the best navigation device: small screen size, short battery life, overheating, piecemeal map coverage, lack of water resistance, no Wi-Fi or cellular data in remote locations, and risk of theft.

A standalone device has county-wide map coverage, and can have better controls and screen brightness adjustment. Most are made by Garmin, Magellan, and TomTom. Also, hand-held units (not meant for city or highway driving) can be waterproof, and run from standard batteries. Should you lose it, you don't also lose your photos and other critical phone information. And in most cases, you can still call for help and check your location on the smartphone when the navigation device runs out of power or fails in other ways.

Get around

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You will need to set the device so it works as a GPS. This will depend on the type of GPS you are using. But the basic way to use a GPS is this: once you've got it working and you've got the destination set, all you need to do is drive and GPS will work out your location as you drive. It will then use your location on the route to determine where next you will need to turn or drive on so you can continue along the GPS's route to the destination.

Check the settings for what routes the device will prefer. If you have a flight to catch or driving conditions are bad, you probably want the "fastest route" instead of "shortest route", but if you want to enjoy the landscape and come in touch with the life in regions you are driving through, you instead might want to avoid the fastest route. There may be other options or possibilities to finetune. Sometimes unpaved roads are not even shown by default, so if you want or need to use them you need to explicitly enable viewing them.

It is advisable that you use your GPS software for some time in familiar areas, so that you get used to it and any quirks it may have. Try also to get into conditions similar to those that may pose challenges at your destination.

Cope

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Although a GPS navigator makes navigation and orientation very much easier in many situations, in some circumstances the information given may be misleading. For example, you're traveling from Pittsburgh to Philadelphia. You enter into the GPS system that you're going to Philadelphia, so the GPS successfully takes you to Philadelphia. But for the GPS "Philadelphia" is not the town, but some more or less arbitrary point in the town (perhaps the geographic midpoint). It will take you there, even if that means driving away from your intended destination by obscure alleys. Giving a suitable exact address avoids this problem.

Topography and accuracy

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Enclosed areas, narrow streets, and unusual topography can cause problems for GPS navigation, which may be less reliable than usual in these areas, as the device gets information from fewer, sometimes none of the satellites. A GPS needs a good portion of at least half the sky to work effectively—clouds and bad weather are not an issue though. Your device may mislead you if signals are blocked by skyscrapers or even the canopy of the Kakamega Rainforest. However, GPS signals can be imagined like sunlight, the more that gets through the better, but a dark room and you are lost.

Lack of accuracy when off-road can apply to both smartphones and standalones. If the device is running a program for driving, it assumes you're on the road (especially Waze), and adjusts the "location cursor" accordingly. Google Maps has a walking mode, but you risk damage to your smartphone if watch it while walking in the terrain. If you can afford it, have three devices capable of receiving GPS: a standalone device for driving, a durable standalone waterproof device for walking and hiking, and a smartphone.

Time zones

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When you enter a different time zone, most navigation systems will detect that and display all times accordingly. However, while setting up a route to a destination located in a different time zone, your estimated time of arrival (ETA) will typically still be displayed according to your current time zone.

Example: You're driving east from Chicago (Central Standard Time, CST, UTC-6) to Detroit (Eastern Standard Time, EST, UTC-5), and you must be there by 3 PM EST. If your ETA during setup in Chicago is anything beyond 2 PM CST, you will be late. Some systems will warn you about this. Some systems will allow you to specify a desired time of arrival according to the destination time zone and then do the math for you – which can be very useful if you need to be at your destination at a certain point in time.

China

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China uses its own coordinate system, which is deliberately obfuscated and different from the international standard, apparently for national security reasons. This means that various foreign GPS navigation programs have problems in China, with locations displayed about 100–700 m from where they should be. Wikivoyage's practice is to use standard (WGS84) latitude and longitude coordinates in all articles, including articles about China, which means that our coordinates should display correctly on OpenStreetMap and other mapping programs that use WGS84, but may display incorrectly on Chinese mapping apps. However, some Wikivoyage articles mistakenly use some Chinese (GCJ) coordinates, which will display incorrectly on Wikivoyage maps and other OpenStreetMap-based maps. The Special Administrative Regions of Hong Kong and Macau use WGS84 coordinates, but for some reason some mapping apps still have problems, especially near the border with mainland China. The result of all of this for travellers is you should be careful when using GPS navigation in China, including Hong Kong and Macau—be on the lookout for offsets of 100–700 m, especially when doing anything that involves interaction between Chinese and foreign data or software. For more details see the Wikipedia article Restrictions on geographic data in China.

Scrambling, jamming and spoofing

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The the provider of the satellites can lower the accuracy of your device at will and anyone with a suitable sender can jam the signal. More advanced attackers can jam the weak satellite signals and send stronger fake GPS signals to make the device believe it is somewhere else. Incidents do happen quite often: it is explicitly stated in certain military doctrines, it happens at high level meetings of politicians, and it seemingly happens also just to cause trouble or to make a political point. This is especially relevant for travellers in times of conflict or around conflict regions. Finland has had to change their airport approach practices because of recurring jamming events, there are general recommendations for aviators to update their procedures and equipment, and boaters on the Baltic Sea have been warned. The issue also affects e.g. hiking near the border between Georgia and Russia – and any navigation near war zones.

When your device loses signal, or the signal gets too inaccurate, you need traditional navigation techniques and a reliable offline map. If you use an autopilot, your car's GPS or other automated systems, you need to be prepared, as they may continue to update your position according to defaults with little connection to reality – for short breaks in the signal, this gives a smoother experience, but in the case of jams, you may not notice until too late.

Stay safe

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If you're driving, be careful of dangerous or remote roads. River crossings, mountain passes and poor road surfaces aren't always taken into account by all navigation software. In some instances, the shortest route might also take you through unsafe areas (for example the shortest from Cape Town Airport to Cape Town City Centre take you through the shanty towns in the Cape Flats). Do a sanity check to make sure you're taking the main road. Try and navigate to an address or a known place. If you're carrying bikes on the roof, don't drive under a low bridge just because a car GPS says this is a fine route. Pay attention to the roads.

If you're using a GPS navigator for backcountry hiking, you just lifted the stakes in the game. You need to check the veracity of the route before you go – against a known reliable source. Open mapping data is often done by armchair mappers from aerial imagery – and mapped trails may lead into fences, steep country, and cliffs that aren't visible from this imagery. Some navigation or orienteering skill and some experience with the device will be needed to identify and handle these situations. And like all electronics, the device can fail, and (you know Murphy's law, don't you!) it may fail at the worse possible moment. Especially paper maps may use coordinate systems other than WGS84 (which is used by the GPS), thus giving a mismatch in positions unless correction data are used. Check beforehand. If you're in England, France, or Spain, don't forget to double check east (+) and west (-) longitude coordinates, as these countries have both. Satellite navigation uses quite a lot of power. Carry a spare battery. Remember that batteries are consumed quickly in the cold. For longer voyages a solar power charger may be an option, but whether its capacity suffices (also in cloudy weather and other less-than-ideal circumstances) and it keeps working is an open question.

Some manufacturers (such as Garmin) market specialised devices specifically for marine use. The underlying satellite signal is the same, but a marine GPS stores nautical charts (usually purchased separately) instead of highway maps. If you take this on the autobahn, it'll display valid coordinates but tell you that you've run aground.

If you're on a boat with a non-marine device, reverse problems apply: some devices may put the marker on a nearby road on the assumption that the location in the water must be due to signal problems. To see the smallest rocks you may have to zoom in so much that you don't get any overview. In low visibility conditions, remember that boats, swimmers, birds and that half-submerged log are not on your map. If you sail in the night and the person navigating is simultaneously lookout, make sure the brightness can be adjusted to dim enough (which is much dimmer than you could imagine in the day).

The device should be usable for the intended use. A device used by the driver should allow him or her to concentrate on the driving. A device used outdoors should be rain and moisture resistant. The controls should be usable also in the field and the display bright enough in sunshine and dim enough in the night.

The device may fail. Also, the signal can be interfered with, such as probably by Russia now and then in the Finnish airspace. You should have some backup, usually including paper maps and paper notes about where you are, including time of and direction since last update (depending on circumstances, good mental notes may be enough). A traditional compass and a flashlight may be a good investment if you plan on traveling far away from infrastructure.

Consider using a computer or tablet with a larger screen for route planning. You can get a wider view than a screen on phone or small GPS. Then you can transfer the route to your smaller device once your planning is done. On a boat you may want to use that larger screen also for actual navigation (check that the devices can communicate: there are different connectors and protocols). It is still hardly ever as large as a paper chart, and zooming out can hide important features.

Privacy

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For technical reasons, it is not possible to track your position using GPS (or GNSS) alone as transmissions only go in one direction: The satellites transmit a time signature and your receiver uses that to calculate your position – that's it. Thus, an old-fashioned hand-held GPS device without mobile network connectivity is not a concern for your privacy.

Things can change quite dramatically, though, when using navigation on your mobile phone. The navigation app has access to your location, and may record your location history or even share it with service providers. Most modern phones allow you to limit which apps have access to your location information. These permissions and limits are found in the phone settings, and it is worth checking to limit apps with location access if you are concerned about privacy.

The future

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L5 signal is slowly being introduced into consumer devices (as of 2023, it is supported by some mainstream phones and other devices). GPS accuracy will be accurate to within a few centimeters, and will work much better in areas with partial sky-cover. On the other hand, interfering with the signal has become a tool in international conflicts, which makes it less reliable.

See also

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This travel topic about GPS navigation is a usable article. It touches on all the major areas of the topic. An adventurous person could use this article, but please feel free to improve it by editing the page.