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Add Marker
Pressing the lower-center button will add a position marker on the map and in the log files.

If you wish to add the marker at your current position, first enter the Map » Follow Me mode.

If you wish to add the marker at any other position, first navigate to it using Map » Move Around mode and/or Map » Zoom in/out mode.

Markers are shown on the map as little targets with various colours.

You can reload markers from a previous log file by following this procedure : How to overlay a log or a track on the map.