The Offline Maps tool can be used to import and manage maps for use without an Internet connection. This tool supports using images, PDFs, and Mapsforge (.map) files.
Map files are not included with Trail Sense and must be created or imported. Here are some common sources of trail maps:
To import or create a map:
.map file from your device. If your PDF contains geospatial data, it will be used for automatic photo map calibration.Once a map is imported, the original file can be deleted if you want to save space.
If a map is imported from an image or non-geospatial PDF, Trail Sense will open the calibration screen.
To calibrate a photo map:
If Trail Sense reports that calibration is invalid, make sure the two map points are different, the two real-world coordinates are different, and the distance between the selected map points is roughly proportional to their real-world distance.
If your map features gridlines:
The intersections of gridlines are the easiest calibration points.
If you have Internet access, you can look up the coordinates of a map feature (e.g., mountain summit, trailhead). Then in Trail Sense, tap the same location on the map and enter the coordinates.
Tap a map in the list to open it.
Photo maps open in the map viewer. You can drag to pan, pinch to zoom, or tap the zoom buttons in the bottom-right. To recenter the map on your screen, click the recenter button in the top-right. The map's scale is shown in the bottom-right.
Click the GPS button in the bottom-right to center a photo map on your location. Clicking it again will lock both your location and orientation, while a final click unlocks it. The compass icon in the top-right always points North.
Trail maps open in a preview viewer. You can drag to pan, pinch to zoom, or tap the zoom buttons in the bottom-right. The preview viewer is limited, so use the Map or Navigation tool with the Trail maps layer for regular use.
By default, photo maps align with North roughly facing up so that the map is square with the screen. You can change this so the map is aligned with North facing up by disabling Settings > Offline Maps > 'Keep map facing up'.
By default, Trail Sense loads more tiles for higher quality when viewing a photo map. You can disable this in Settings > Offline Maps > 'High detail mode' to reduce memory usage at the cost of lower quality.
Layers are used to display information on the map. For more information on layers, refer to the 'Map Layers' guide.
Photo maps are shown by the "Photo maps" layer. You can't disable this layer when viewing a photo map.
Trail maps (Mapsforge) are shown by the "Trail maps" layer.
You can organize maps into groups. To create a group, click the '+' button in the bottom-right of the map list and select 'Group'. Give the group a name and click 'OK'. To add maps to the group, click on the group in the list and follow the map import instructions. The map will be added to the chosen group.
To change the group of an existing map, click the menu button on the map row you want to move, select 'Move to', and choose the target group.
To rename a group, click the menu button on the group row you want to rename, then select 'Rename' and provide a new name.
You can delete a group, along with all maps within it, by clicking the menu button on the group row you wish to remove, then selecting 'Delete'.
To search through your maps, use the search bar at the top of the map list. This search includes the current group and all subgroups.
To sort maps by distance, time, or name, click the menu button in the top-right and select 'Sort'.
The preview of a photo map is displayed on the left side of the map row. You can disable this preview in Settings > Offline Maps > 'Show map previews'. Map previews only display for images and PDFs.
To rename a map, click the menu button on the map row you want to rename, then select 'Rename' and provide a new name.
You can also rename a photo map by opening the map, clicking the menu button in the top-right, and choosing 'Rename'.
You can choose which maps are visible on map layers by clicking the eye icon on the right side of the map row.
To show or hide all maps in a group, click the menu button on the group row and select 'Show all' or 'Hide all'.
To delete a map, click the menu button on the map row you want to remove, then select 'Delete'.
You can also delete a photo map by opening the map, clicking the menu button in the top-right, and choosing 'Delete'.
If you've created beacons, they will appear on photo maps.
When navigating to a beacon, the distance, direction, and estimated time of arrival (ETA) are displayed at the bottom. A line is drawn from your location to the beacon. To cancel navigation, click the 'X' button. You can open the beacon by tapping the beacon name in the navigation sheet.
You can initiate navigation from a photo map by tapping a beacon or long-pressing a map point and selecting 'Navigate'.
To create a beacon from a photo map, long-press a map point and choose 'Beacon'. This opens the 'Create Beacon' screen with the location filled in.
For further details on beacons, refer to the 'Beacons' guide.
If you've created paths, they will be visible on photo maps.
To create a path from a photo map, follow the instructions in the 'Measuring distance on a photo map' section below.
For further details on paths, refer to the 'Paths' guide.
You can measure distances on a photo map by opening the map, clicking the menu button in the top-right, and selecting 'Measure' or 'Create path'. Tap the map to place markers, and the total distance will be displayed at the bottom. To undo the last marker, click the undo button in the bottom left. Cancel by clicking the 'X' button in the bottom-right. You can also convert the drawn path into a saved path by clicking the 'Create path' button at the bottom.
For a quick measurement from your location to a point, long-press that point on the photo map and click 'Distance'.
Long press a location on a photo map to view the elevation from the DEM.
To recalibrate a photo map, open the map, click the menu button in the top-right, and choose 'Calibrate'. Follow the instructions above to recalibrate.
If your photo map points are not aligning correctly while calibrating, try calibrating again with different points first. If they still do not align, open the map, click the menu button in the top-right, and select 'Change projection'.
Changing the projection while calibrating will clear any unsaved changes.
To export a photo map, click the menu button on the map row you want to export, then select 'Export'. You can also open the map, click the menu button in the top-right, and choose 'Export'. This action exports the map as a PDF, and if calibrated, it will convert it into a geospatial PDF.
To print a photo map, click the menu button on the map row you want to print, then select 'Print'. You can also open the map, click the menu button in the top-right, and choose 'Print'. This opens the system print dialog, enabling you to print the map.
To trace a photo map, open it, click the menu button in the top-right, and choose 'Trace'. Move into a shady area or block out the sun using a cloth and place paper over your screen so that you can see the map through the paper. Use a pen or pencil to trace the map, but avoid markers or pens that can bleed through the paper. Be careful not to slide the paper while tracing.
Bottom navigation will be disabled until you turn off trace mode.
When you are finished tracing, click the lock icon in the bottom-right to turn off trace mode.
To alter the resolution of a photo map, click the menu button on the map row you want to adjust, then select 'Change resolution'. A dialog will appear, allowing you to switch between low (lowest quality and smallest file size), medium (moderate quality and file size), and high (highest quality and largest file size) resolutions. Keep in mind that changing the resolution is a permanent action and cannot be undone.
By default, Trail Sense will automatically reduce the map resolution on import. To change this, disable Settings > Offline Maps > 'Reduce photo resolution' or 'Reduce PDF resolution'.
Some trail map files include attribution. To edit attribution, click the menu button on the map row, select 'Attribution', and provide the attribution text. If attribution is populated, it will be shown on the map when the layer is displayed.
You can enable the Open Photo Map quick action in the settings for the tab where you want it to appear.
To use the quick action, tap the quick action button and the active photo map will be opened and locked to your location. If no photo map is active, the map list will be displayed. Long press the quick action to open the Offline Maps tool.
If you prefer a video guide on using photo maps, here's a video by one of Trail Sense's users: YouTube: Turn Photos into Navigational Maps with Trail Sense! by DeathfireD
Maps are only as accurate and current as the map file you imported or calibrated. Always carry a physical map and compass as a backup, and verify important navigation decisions with your surroundings.