Key Concepts

A few concepts that appear throughout JBalloonNav.

GPS Lock

When GPS Lock is active, your position stays fixed on screen and the map moves underneath you. When off, you can pan the map freely and your position marker moves.

Reference Point

A reference point is a waypoint you've designated as your current target. When set, the status bar can show bearing and distance to the reference point. Useful in competitions for navigating to a target.

To set a reference point, open the waypoint list and long-press a waypoint.

Predictive Track

The predictive track line shows where you'll be carried by the current wind, based on your current speed and heading. The default lookahead is 15 minutes (configurable in Settings → Tracking → Predictive Track Length).

The line alternates colours for each time segment, making it easy to estimate when you'll reach a particular point.

Units

JBalloonNav supports multiple unit systems, configured in Settings → Display:

Measurement	Options
Height / Altitude	Feet, Metres
Distance	Kilometres, Miles, Nautical Miles, Mixed
Position	Degrees, Degrees-Minutes-Seconds, UTM, British National Grid
Speed	Derived from distance/time units

Coordinate Formats

Tap the position display field to toggle between your current format and Degrees/Minutes/Seconds. Useful when your display is set to UTM or OS Grid but you need to read out a lat/lon to someone.

Status Bar Customisation

The status bar at the top of the map shows several data fields (position, altitude, speed, bearing, etc.). Long-press any field to change what it displays. For example, you can replace the position field with flight time, or the distance field with time-to-waypoint.

In landscape orientation, additional fields appear for the active waypoint (bearing, distance, time).