How to prepare offline maps for field work without internet
Field work should not stop when internet disappears, but offline preparation must happen before leaving.
Field takeaways
- Capture, drawing and export can work offline; online basemaps and live corrections need connectivity.
- Download the work area map before the field day.
- Keep KML, DXF, CSV and project files on the phone.
- NTRIP/RTK live corrections may need internet.
- MapLab Survey preserves layers, notes, photos and exports offline.
Positioning does not need the internet
GNSS works from satellites, so location, measurement, calculation and export all continue without a connection. What disappears is the base map. Knowing that distinction prevents panic on a site with no coverage — the app has not broken, there is simply no connection to fetch map tiles over.
The checklist before you leave
- Cache the working area at the zoom levels you will actually use.
- Load reference KML, KMZ, DXF and CSV files while you still have coverage.
- Check the coordinate system and the layer names.
- Check battery, power bank and device storage.
- If RTK is planned, settle the correction connectivity plan in advance.
What still works offline
In MapLab Survey, drawing, measuring, notes, photos, area, distance, profiles and file export can all run without a connection. Live base map refresh, cloud sync and NTRIP corrections may need one. Live NTRIP depends on the mobile network; without it, plan for a local base station or accept lower accuracy — and make that decision in the office, not in the field.
Battery is the real constraint
Out of coverage a phone drains itself hunting for a network. Use flight mode with GNSS on and carry a power bank. A battery that dies at noon costs more work than any missing map tile.
Plan for the outage
Mountains, mines, fields, forests and rural sites do not promise coverage. Plan the day as if the connection will drop, not as if it will hold. Offline preparation takes ten minutes the evening before and saves a full field day the morning after.
Try these steps on your own phone.
MapLab Survey handles RTK/GNSS point capture, drawing, area and volume calculations and coordinate conversion, then exports to DXF, KML/KMZ, GeoJSON, Shapefile, GeoPackage, NCZ or CSV. Capture, calculation and export work offline. Live NTRIP corrections and online basemaps need a connection.
Frequently asked questions
How do I prepare offline maps?
Download the work area before field work.
Can measurement work offline?
Yes, capture and export can work offline.
Does RTK need internet?
NTRIP corrections usually do.
Can KML open offline?
Yes, if the file is on the device.
Technical references
The field guidance in this article is aligned with the technical and official references below.
Related: Offline field surveying · Open KML file · GPS track recording · MapLab Survey