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Gadget 03 · Navigate without data

Offline maps

Many people believe that without data their phone doesn't know where it is. Not true: GPS receives satellite signals with no internet at all. What's missing is the map, and you can download it in advance for free.

2 min read · Reviewed on

How GPS works without internet

Your phone's receiver listens to signals from several satellite constellations, such as GPS, Galileo or GLONASS, and calculates your position. It only receives, it sends nothing, so it needs no coverage or data.

The internet is only used for two things: downloading the map and speeding up the first fix. Without data, the first fix can take a minute or two, especially indoors. Step outside to an open spot and wait.

Step 1: download maps on your phone, for free

These apps use free OpenStreetMap data, which often includes trails, springs and paths missing from other maps:

  • Organic Maps: very simple, with no ads or tracking. Download your country or region and you're set.
  • OsmAnd: more complete, with contour lines, routes and many layers. Great for the backcountry.
  • Google Maps also lets you save offline areas, though with less detail outside cities and they expire.

Do it today

Download the map of your state or region and the route to your out-of-town meeting point. Mark your home, meeting points, hospitals and water sources. When you need it, you won't be able to download it.

Step 2: a paper map

Experts agree: phones run out of battery, get wet or break. A paper map of the area within a one- or two-hour drive, in a waterproof bag, never fails. If you can only carry one thing, a map is more useful than a compass.

Step 3, optional: a handheld GPS

A dedicated GPS makes sense if you hike, live in a rural area or want a tool that doesn't depend on your phone:

  • It runs on AA batteries, which you can buy anywhere or carry as spares. A phone needs an outlet.
  • More resistant to water, cold and knocks.
  • Operated with buttons, even with gloves or in the rain.

Garmin eTrex 22x

The best-selling entry model: color screen, preloaded maps and about 25 hours of battery life on two AA batteries.

Garmin eTrex 32x

Same as above, plus an electronic compass and barometric altimeter. Useful in the mountains and in fog.

If you also need to communicate

Neither GPS nor maps send your position to anyone. For that you need a satellite messenger, which combines maps, messaging and SOS, or a personal locator beacon.

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