Walking without a signal

Historic hikes go through places with poor reception — under bridges, inside forts, deep in a park. Trail mode is built to keep working there.

It downloads automatically

Tapping start the hike saves that hike to your phone: the stops, the stories, the photos, the route and the map around it. You do not press anything to make that happen. See The map below.

A bar across the top reports progress, including the size of the map being saved, then confirms Saved for offline use and disappears. If it says the download was incomplete, the download button in the top bar retries it — that button is a repair, not the normal way to get a copy.

What works offline

• Every stop, story and photo (photos are saved in a smaller size, see below)
• The route line, the numbered stop pins and the direction arrows
• Your position on the map, if you turned it on
• Moving between stops, and the map following you
• The street map around the route, for hikes that have a saved map (see below)
• Answering quiz questions
• Recording a marker you found, if you are signed in. It is saved on your phone and sent when you have a signal; see below.

What waits for a signal

• Quiz grading. Answering offline records your choice and tells you it is saved, but does not tell you whether it was right — grading happens on our server, which is what keeps the answers out of the phone in the first place. Your answers grade themselves when you reconnect.
• Logging a completed hike, rating, and reporting a problem with a stop.
• Sending a marker you found. Without a signal, tap Save on this phone. Trail mode says Saved on this phone, sends when you have a signal, the stop shows how many markers are waiting, and they are sent by themselves the next time trail mode is open with a signal. Is it one of these? is skipped offline; the site checks for the same marker when yours arrives. See Finding markers.

Photos

To keep the download small, the photos are saved to your phone in a smaller size. With a signal, trail mode shows the sharper version when you open a photo full screen. Without one, it shows the smaller saved copy, which is still clear on a phone screen.

The map

For most hikes, the street map behind the route is saved to your phone with the rest of the hike, covering the trail and a short way around it, plus a wider, less detailed area around that for when you zoom out. It is a modest download, up to about 10 MB, and the bar at the top shows its size while it saves. Once it says Saved for offline use, the map works with no signal at all. Zooming out stops a few miles beyond the trail, because that is all that was saved. For a very large hike the wider area may be smaller to keep the download down.

A hike that does not have a saved map yet falls back to the regular street map. That one only keeps the areas you looked at while you had a signal, so without a signal it may not load.

The route line, the stop pins, the direction arrows and your position always work offline either way. The satellite view is never saved for offline use and needs a signal.

Installing it like an app

On most phones you can add the site to your home screen from the browser menu. It then opens without browser chrome, which gives you more screen for the trail.

Offline downloads and shared devices

Downloading works the same whether you're signed in or not, for any hike that's actually published — what you can walk offline is what anyone could see on that hike's page. A maintainer previewing their own unpublished changes is the one exception: that preview is never saved for offline use, so it always needs a signal.

On a shared or public computer, signing out clears what you saved for offline use, along with your progress through a hike on that device, and so does a different account signing in. Whoever uses it next only ever sees their own downloads and their own place on the trail, so sign out when you finish on a device that isn't yours.

Two changes keep your progress instead:

• Signing in partway through a hike you started as a guest: your progress moves onto your account.
• Being signed out because you were away for a while, without signing out yourself: your place and your offline copy stay on the device, so you can pick up where you left off and sign back in.

Markers waiting on the phone to be sent are always cleared when the account changes, signing out and a session ending included. They are never sent under someone else's account.