Gold Prospector

Field guide

Offline Maps

Download the ground you plan to work while you still have signal. In the field, the map runs off your phone with no service at all.

  • Every layer downloads, including LiDAR
  • About 28MB per square mile cell
  • No signal needed once it is saved
The download grid over satellite imagery with three cells highlighted, the panel showing three cells selected and about 84 MB total
Select the cells covering the ground you plan to work and hit the download button.

What downloads

Every layer, not just the basemap.

  • Satellite imagery
  • Both LiDAR hillshades
  • All three historic topo bands
  • Property lines
  • Active and closed mining claims
  • Public lands

Step by step

  1. Step 1 of 4

    Open Offline Maps

    On the map screen, tap the offline maps button. It is the dashed square in the lower left, above the info button.

    The map screen with the offline maps button, a dashed square icon, in the lower left corner

  2. Step 2 of 4

    Tap Download a Region

    Saved areas are listed underneath, along with the storage they use. This screen is also where you come back to activate one later.

    The Offline Maps panel with the Download a Region button, and saved maps listed below it

  3. Step 3 of 4

    Pick your cells and download

    Zoom in until the grid appears. It only shows at closer zoom levels, because each cell is about a mile across. Tap the cells covering the ground you plan to work, then hit download and give it a name.

    Budget about 28MB per cell. Keep the app open and the screen on until it finishes. If you background the app or the screen locks, the download stops.

    The download grid over satellite imagery with three cells highlighted and the panel showing three cells selected, about 84 MB total

  4. Step 4 of 4

    Tap the saved map to use it

    Open Offline Maps and tap the map you saved. The banner at the top tells you which area is active, and the map draws only from what you downloaded.

    That phone is in airplane mode. No signal at all, and the LiDAR still renders. Tap the X on the banner to go back to the live map.

    The map in offline mode over LiDAR hillshade, with a banner reading Offline, North Fork, and the phone in airplane mode

Downloading is only half of it

A downloaded area does nothing on its own. You have to open Offline Maps and tap the saved map before the app will use it.

If there is no banner at the top, you are still on the live map and still waiting on a network that is not there.

Knowing where your coverage ends

Inside offline mode, panning past the edge of what you downloaded shows nothing. That is how you tell where your coverage stops.

Wifi or cell service

Wifi is best, and it is the fastest way to pull down a few cells. It will also download over regular cell service, so being away from the house does not stop you.

Either way, do it before you lose signal. The trailhead with one bar is not where you want to start a download.

Managing saved areas

Downloaded areas can be renamed and deleted. The screen shows total storage used.