Can you trust free map apps?

Missing information and non-existent trails have led some walkers into trouble when relying on free map apps for navigation and hiking, Which? Travel finds.

Keswick Mountain Rescue have been repeatedly called out by lost hikers who used the likes of AllTrails, Komoot and Maps.me. 

These free apps all source their data from OpenStreetMap (OSM) – which is crowdsourced. This allows a global community of volunteers – with varying levels of expertise – to add or edit routes as they see fit. 

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Missing trails on free map apps

Keswick Mountain Rescue detailed  two incidents in two days involving popular hiking app AllTrails. 

The first, on Causey Pike in the Lake District, involved a walker following a path on the app that didn’t exist. It took five members of the rescue team almost two hours to get him back to safety.

The non-existent trail was subsequently removed from the apps, but the very next day a second walker became stranded and frozen with fear (or ‘cragfast’) on Barf fell. Unlike the Causey Pike incident, this was a genuine path. But the hiker had failed to glean from the app just how challenging the climb was. 

Craig Dring, from Keswick Mountain Rescue, told us: ‘Barf is a real black spot for us. It’s like a scree slope (loose slate and rocks that fall away as you climb). People who are unfamiliar with the area shouldn’t put all their faith in map apps. They aren’t reliable enough and they don’t have the topographical detail to get you out of trouble.’ 

It’s not only a problem in the UK. In 2022, Canada’s search and rescue services in Alberta Parks responded to more than 300 incidents involving map apps. They claim that accuracy isn’t so much the problem, but a lack of detail. Not only does that make the app tricky to follow, but the difficulty of the terrain isn’t always clear. 

Some apps include only basic contouring to show how steep a trail is, while others don’t include it at all. This can lead to hikers biting off more than they can chew.

What OpenStreetMaps told us about free maps

When we approached OpenStreetMaps (OSM), it told us that the app makers themselves decide how much detail to include in their maps. Some features, such as terrain data, aren't provided by OSM and must be sourced elsewhere.

It added: ‘This is a rapidly evolving technical and cartographic application, and would benefit from more collaboration and less finger pointing… No one is claiming OSM is perfect, and any other map data that makes that claim is deceiving. Data in OSM can be discussed and debated. The result is the best map around.’

Want to rely on more than a map app? These are the best providers for a guided or self-guided walking holiday.

OS Maps: the solution?

There is another option, if you are prepared to pay for it. Government agency Ordnance Survey (OS) maps the UK and is recognised as one of the best in the world. 

Its data is updated as often as 30,000 times a day and is accurate to within 5cm, with information provided by aerial photography and 230 surveyors on the ground. Field boundaries and topographical details are clear and there are more navigable features, such as railway lines and footbridges. 

Even churches have a different symbol depending on whether they have a tower or a steeple. Helpfully, OS also designates whether a path is a byway, bridleway or public footpath. 

All of this translates to an easier-to-read map. The downside is that it costs £35 a year to subscribe to its premium service. 

You can access standard mapping for free, but you can’t get the most detailed maps, or print or download any of its trails to use offline. It also shares the same limitations of all apps used as maps. In heavy rain it can be impossible to zoom in to see where you’re going, or your battery could run out altogether if the trail takes longer than expected.

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Paper maps vs map apps

It could explain the recent surge in popularity for old-fashioned paper maps. In 2020, OS reported that sales of its custom-made maps increased by 144% and it has led to new innovations. SplashMaps produces all-weather fabric maps that can be scrunched into a pocket or bag, or even worn. 

Founder Steve Overton uses Ordnance Survey data for his UK maps, but relies on OpenStreetMap for the rest of the world. He argues that even with ‘a few flaws’, open-sourced mapping is important because it provides data for locations all over the world and free of charge.

Open-source map apps are a fantastic resource for exploring the outdoors and will be sufficient for many locations. But they’re not always accurate and may not include the level of detail needed for more complex or remote hikes. Read our tips below to avoid getting into trouble. 

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5 tips for walkers when choosing a map

1. If you do use a physical map, make sure you know how to read it.
2. Check the weather forecast and dress accordingly (or if it’s even safe to proceed at all). And if heavy rain is forecast, consider whether your phone will be usable. 
3. Fully charge your phone and take a backup battery.
4. Whatever map you plan to use, tell somebody where you’re going and when you expect to be back.
5. In an emergency, call 999 and ask for the police, then mountain rescue.