The best open source Map alternative to Garmin Connect is Turtle Sport. If that doesn't work for you, our users have ranked more than 50 alternatives to Garmin Connect, but unfortunately only one of them is a open source Map Service. If you can't find an alternative you can try to remove all filters.
Turtle Sport is an open source software developed to communicate with GPS devices : Garmin, Suunto, etc. The following functions are available:
Retreive your activities from GPS devices. Import and export activities in GPX, hst, tcx, kml, fit. Configure the athlete data: weight.
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