CalTopo planners working in the field
Carry CalTopo Exports on Your Phone: A Free Field Companion Workflow
CalTopo is a powerful planning environment for desktop maps, printed products, and advanced layers. A field day can still benefit from a simpler phone companion: carry the approved route or boundary offline, follow it on the ground, and capture observations that belong in the next planning revision.
Export only what the field team needs
Export the relevant route or data layer from the planning workflow in a portable format such as GPX or GeoJSON, then import it to the phone. Keep a version name and date so the team can tell which plan it is carrying.
Do not try to mirror every desktop layer on a small screen. Field use improves when the map shows the route, the boundaries or points that affect decisions, and enough offline basemap context to navigate.
Check the plan on the ground
Follow or record the route as appropriate for the assignment. Add waypoints for conditions that change the planning picture: a closed access road, a washed crossing, a useful staging spot, or a location needing a new layer or note.
Mapper.one can provide route-following and offline map context, but it does not replace CalTopo’s desktop analysis, printing, team coordination, or specialized layer stack.
Return observations to the planning workflow
At the end of the visit, review the recorded track and notes while they are fresh. Move approved observations back into the team’s planning system rather than leaving the phone map as the only record.
This division of labor is useful: plan deeply on the desktop, carry a focused map in the field, then let field observations improve the next plan.
Common questions
Questions from the field
Which CalTopo exports work well on a phone?
GPX is commonly used for routes, and GeoJSON works well for points, lines, and boundaries. Mapper.one can also import KML and KMZ.
Does mapper.one replace CalTopo?
No. CalTopo remains the stronger desktop planning and analysis tool. Mapper.one is a lightweight, free phone companion for carrying selected data offline.