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Release 1.0.49

Live Navigation Mode

Live Navigation Mode turns Luna Marine Charts into a real-time navigation display by using your device's GPS position updates to track your vessel on the chart. As GPS data is received, the app continuously calculates your Speed Over Ground (SOG) and Course Over Ground (COG), then applies smoothing algorithms to reduce sudden jumps and provide a steadier, more readable display.

This mode is designed to help you monitor your vessel's movement, follow a planned route, and view key trip information at a glance while underway.

How it works

• GPS position updates provide the vessel's current latitude and longitude.
• Speed Over Ground (SOG) is calculated from changes in position over time and displayed as a smoothed value for better readability.
• Course Over Ground (COG) is calculated from the direction of travel and smoothed to reduce erratic heading changes caused by GPS noise.
• Position smoothing uses recent GPS updates to produce a more stable vessel position on the chart.
• Route calculations use the vessel's projected position on the selected route to calculate remaining distance and estimated time of arrival.

Chart display

When Live Navigation Mode is active, several visual elements appear on the chart to help you understand your current position and route progress.

• Red vessel arrow – Represents your boat's current position and direction of travel.
• Magenta route line – Shows the active route you have selected.
• Magenta waypoint discs – Mark each waypoint along the route.
• First waypoint – Displayed with a white outline to identify the starting point.
• Final waypoint – Displayed with a red outline to identify the destination.
• Live track updates – The vessel's position along the route is updated continuously as GPS data is received.

Instrument Panel

The instrument panel along the bottom of the screen provides quick access to the most important navigation information for your trip.

Speed Over Ground (SOG)

Displays the vessel's smoothed Speed Over Ground, which represents the boat's actual speed relative to the Earth's surface. Smoothing helps reduce short-term fluctuations caused by GPS signal variation.

Course Over Ground (COG)

Displays the vessel's smoothed Course Over Ground, which represents the boat's actual direction of travel over the Earth's surface. This is based on recent movement and may differ from the boat's compass heading if wind, current, or drift are affecting the vessel.

Route Estimated Time of Arrival (ETA)

Displays the estimated time remaining and estimated time of arrival for the active route.

• The vessel's current position is projected to the nearest point on the selected route.
• Remaining time is calculated using the vessel's current smoothed SOG.
• Tap this panel to toggle between ETA for the entire route and ETA to the next waypoint.

Route Distance

Displays the remaining distance and total route distance for the active route.

• The vessel's current position is projected to the nearest point on the selected route.
• Remaining distance is calculated from that projected position to the end of the route.
• Tap this panel to toggle between distance for the entire route and distance to the next waypoint.

Position

Displays the vessel's current latitude and longitude as determined by the GPS receiver. These coordinates update continuously while Live Navigation Mode is active.

Notes

• SOG and COG are based on GPS movement and are most reliable when the vessel is moving steadily.
• At very low speeds, COG may fluctuate because small GPS position changes can have a larger effect on calculated direction.
• ETA calculations assume the vessel continues at approximately its current smoothed SOG.
• Live Navigation Mode requires GPS access and may be affected by signal quality, device hardware, and environmental conditions.