Offline Maps for Hiking: How to Not Lose the Map When You Lose Signal

The Misunderstanding

People say their phone does not work in the mountains. Two different things are being described and only one of them is true.

GPS works everywhere. It is a one-way signal from satellites. Your phone receives it in a canyon, in a wilderness, in airplane mode, with no carrier at all. It knows where it is.

The map does not. Map tiles stream from the internet. With no signal there is nothing to stream, so you get a correct blue dot floating on a grey rectangle.

The fix is downloading the map area before you leave service, and it takes about ninety seconds.

How to Download, App by App

AllTrails

Offline maps are part of the paid AllTrails+ tier, not the free one. Open the trail, use the download option, and do it while you still have bars. It does not happen automatically when you press record, which is where people get caught.

What AllTrails is genuinely good at is finding a trail near you with photos and recent condition reports. What it is weaker at is anything off a named trail, because the map underneath is thinner than a topo app's.

Gaia GPS

Select an area, pick your layers, download. The free tier covers the base topo layers and is enough for most day hiking. The paid tier adds the layers that matter for backcountry work: land ownership, motor vehicle use, slope angle, historic USGS quads and National Geographic sheets.

Download each layer you want. Downloading the road map and expecting contours to appear is a common surprise.

Avenza Maps

Free, and the reason to have it is that agencies publish georeferenced PDFs. The National Park Service, the Forest Service and many state parks put out official maps you can load and then see your own position on, offline, at no cost.

This is the best free option nobody uses.

Organic Maps and OsmAnd

Both free and open source, both built on OpenStreetMap, both fully offline once a region is downloaded. Trail coverage varies by how much local mapping has been done, which in the western United States is often surprisingly good.

Google Maps

Downloads a rectangle for offline driving. Roads, towns and fuel, not trails. It is the layer for getting to the trailhead, not the one for the walk.

Battery, Which Is the Real Failure

Navigation almost never fails because the app was wrong. It fails because the phone died.

• Airplane mode. A phone with no signal burns power hunting for a tower. Airplane mode stops that and GPS still works.
• Screen off. The display is the drain, not the receiver. Check position and put it away.
• Keep it warm. Lithium batteries lose capacity fast in the cold and a phone can drop from 40 percent to dead in minutes at altitude. Inside jacket, not outside pocket.
• Carry a bank. A small one covers a weekend. Anything longer, size it for the days between charging.

What to Carry Beyond the Phone

For a marked day trail with other people on it, a downloaded map and a charged phone is a reasonable system.

Past that, the phone becomes one item in a set rather than the whole plan:

1. Downloaded digital map, as the primary.
2. A paper map and a compass, and the ability to use them together. A compass you have never taken a bearing with is a decoration.
3. A satellite messenger for anything remote or solo. Phones now do emergency satellite texting in some regions, which is a genuine improvement, but a dedicated device works where the phone does not.
4. A plan somebody else has, with your route and your expected return. This is free and it is the item that most often ends a search quickly.

Before You Leave the Car Park

A four-item check that takes a minute:

• Map area downloaded, and you have opened it once in airplane mode to prove it.
• Phone at full charge, battery bank in the pack.
• Paper map in a pocket you can reach in the rain.
• Someone knows the route and when to worry.

Everything after that is walking.