... the user friendly GPS tool

Are there plans to make the map available offline?

Yes. RouteConverter was originally based on the Google Maps API and additionally uses Tile-Server from OpenStreetMap and other projects to display the map and the overlays for tracks, routes and waypoint lists. I've been successfully replacing this with a mapsforge based map with offline elevation- and routing services.

There are still gaps regarding the functionality: augmenting positions with place information, finding places, adding positions and the RouteCatalog depend on webservices, too.

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