The best Map alternative to Slopes is OsmAnd, which is both free and Open Source. If that doesn't suit you, our users have ranked more than 10 alternatives to Slopes and three of them are Map Services so hopefully you can find a suitable replacement. Other interesting Map Service alternatives to Slopes are Trekarta and Contours.
Navigation app offering offline and online OSM-based maps, turn-by-turn voice direction, driving, cycling, and walking modes, POI search, GPX track management, map overlays, monthly map updates by country or region, speed and safety features, and location sharing.
Supports offline vector maps for hiking, cycling, geocaching, boating, off-roading, skiing, and skating. Records tracks in the background, provides activity-specific map modes, elevation contours, hillshades, custom places, and map filtering for clarity and sharing.
A ski, snowboard, backcountry and touring tool to discover mountain locations and inspiration for new adventures and to let you track and log your adventures with your phone's inbuilt GPS and camera.
Netherlands
EU
Russia