Sygic Travel Maps - Itinerary planner for independent travelers
Louvre Museum Online - Explore the entirety of the Louvre's collection for free
Detour - Immersive audio walks, now in 17 cities
Sketchfab for Museums - Browse thousands of cultural artifacts in 3D and VR
Foursquare 10 - Your ultimate city guide, in your pocket
Virtual Museums - Explore the world's museums, virtually.