Your iPhone's GPS delivers position and track — locally, without cellular. In NauticCalc it is the context for the logbook and the manoeuvre detection. This guide shows how to grant GPS access, watch for clean accuracy and link the position to the logbook.
Prerequisites
- iPhone with GPS
- Location permission for NauticCalc
- A clear view of the sky for a stable fix
Step 1: Enable GPS
Open GPS position and allow location While Using the App. GPS works without cellular too — the reception comes from the satellites, not the network.
Step 2: Check accuracy
Wait for a stable reading before you rely on the position. Below deck or in tight harbours the fix can take longer or jump — then it is better to measure on deck.
Step 3: Link the logbook
In the Logbook many manoeuvres are recorded with position and time — automatically and locally, with no cloud tracking by us. This creates a traceable trail of your passage.
Step 4: Keep an eye on the battery
Continuous GPS use and the display cost power. On longer legs a charging port is worthwhile so the position recording does not break off.
Common mistakes
- Allowing location only "once" instead of "while using"
- Taking a position below deck on a weak fix
- Expecting GPS to need cellular
- Underestimating the battery and losing the recording
Read next: Logbook export guide · Offline