OpenMaps!

OsmAnd is a map and navigation application with access to the free, worldwide, and high-quality OpenStreetMap data.Enjoy voice and optical navigator, viewing POIs (points of interest), creating and managing GPX tracks, using contour lines visualization and altitude info (through plugin), a choice between driving, cycling, pedestrian modes, OSM editing and much more.

MAPS.ME offers the quickest offline maps of all the countries of the world. Travel with full confidence: wherever you are, MAPS.ME addresses all your offline mapping needs.

With Street View you can explore the world at street level.

Maps gives you turn-by-turn spoken directions, interactive 3D views, and Flyover. All in a vector-based interface that scales and zooms with ease.Maps also gives you guidance to take public transportation and helps you explore your surroundings, so you always know what's around you.

Modest Maps is a small, extensible, and free library for designers and developers who want to use interactive maps in their own projects. It provides a core set of features in a tight, clean package with plenty of hooks for additional functionality.

Navit is an open source car navigation software for Linux, Windows systems and portable devices. It will display your position on a map (in bird-view mode or as a 3D "visualization") from GPS sensor data, and can provide precise route calculation, touch screen functionality and supports Points of Interest (POI), which can be extended via an easy to use plugin system. Unlike other navigation systems, Navit maps are dynamically generated in real time from vector data. Navit is completely offline and works without an internet connection. Navit respects your privacy and does not track your position. »

TransforMap works towards an online platform for you to visualize the myriads of alternatives to the dominant economic thinking on a single mapping system.

KeplerJs is a open source geosocial solution that lets users share favorite places and join discussions in real-time. It can be seen as a platform where users can interact with other open data platforms searching across OpenStreetMap, Geonames among other sources.

AddressToGPS is an open-source tool to search for an address, location, or area using the Google Maps javascript API. Once you have selected a location you then can get the coordinates and open the location in a maps app (OsmAnd). This tool does not require your location, only an internet connection.

GPS Navigation & Maps - Scout (formerly known as "skobbler") contains premium turn & voice guidance, dynamic INRIX traffic intelligence and rich global maps and travel guides.

Magic Earth is a free turn-by-turn navigation app with downloadable maps and speed cameras alerts.