Offline Maps for Fieldwork on iPhone & iPad

How to use your iPhone or iPad as a fully offline GIS field tool — no cell signal, no Wi-Fi, no problem.

Fieldwork happens in places where cell towers don't reach. Remote forest plots, offshore survey sites, mountain valleys, underground utilities — the list is long. If your mapping tool requires an internet connection, it fails exactly when you need it most. GoGIS is designed from the ground up to work offline. Your layers, your data, and your GPS all function without any network connection.

Why Offline Matters for Field Mapping

GoGIS stores imported layers and collected records on your device. You can view local vector data and record observations without signing in to a cloud service. Basemaps and other online services need separate preparation or an internet connection.

Imported vector data stays on your device. Prepare any supported basemap downloads while you have a connection, then check the area before leaving coverage.

Basemap Downloads and Coverage

Built-in basemap downloads are available for supported USGS sources in the United States and GSI sources in Japan. Choose a supported source in Offline Maps, select the area and download it while connected. Elsewhere, imported vector data remains available offline, but GoGIS does not currently provide built-in basemap downloads.

Offline Maps setup showing USGS Imagery, the selected area and estimated download size. — Download the supported basemap for your work area before leaving coverage.

Madison parcel data displayed over downloaded imagery, with airplane mode shown on the iPad. — Parcel layers and downloaded imagery in the field.

Do not rely on recently viewed Apple Maps imagery being available offline. Use the supported download workflow when your project needs an offline basemap.

GPS Works Without Internet

Satellite positioning can work without cellular service on devices with a GNSS receiver. Wi-Fi-only iPads do not have built-in GPS/GNSS. Check your device and the reported accuracy before collecting, and test the project without a connection before leaving for the field.

GoGIS shows your real-time accuracy estimate on screen. In open sky conditions, expect 3-5 meter accuracy — comparable to most dedicated handheld GPS units. This is more than sufficient for field mapping, asset inventory, environmental monitoring, and similar tasks.

Collecting Data Offline

With your layers prepared, use the GPS collection control to record a point, fill in the form, and save it locally. A cellular connection is not required to save the observation. Review the location accuracy before recording the point.

Collecting a GPS point without cell coverage — A sampling grid in airplane mode — GPS blue dot active, nearest point highlighted in orange, all data saving locally.

You can collect hundreds or thousands of points in a single offline session. The SQLite database handles large datasets efficiently, and performance does not degrade as the feature count grows.

What Happens When You Reconnect

Your locally saved records remain available when connectivity returns. Export the layers in the format your team needs, or use Field Sync to exchange changes with nearby devices. Sharing by email or an online service requires a connection.

Tips for Preparation

Cache your basemap — browse the project area on Wi-Fi at the zoom levels you need
Load all layers beforehand — import shapefiles, GeoPackages, or KML files before leaving the office
Charge your device — GPS and screen usage drain the battery; bring a power bank for long field days
Test in airplane mode — verify everything works before you drive two hours to a remote site