OpenStreetMap-based mobile apps

Android apps: OsmAnd~ (F-Droid) OsmAnd (Google Play Store) CoMaps (F-Droid) CoMaps (Google Play Store) and others
iOS apps: OsmAnd CoMaps and others

A number of mobile map apps for orientation have been built based on OpenStreetMap data. Beyond navigation and search, many of these also offer the additional benefit of working offline, as they can download and store OSM data locally.