Google Street View - With Street View you can explore the world at street level.
Glympse - Glympse is the easy way to safely share your location in realtime. No sign-up needed.
GeoGuessr - GeoGuessr is a new way to explore the world in a gaming style.
Wherezat - Wherezat is Fast, free, and easy way to share your location with your friend or family.
OpenStreetCam - OpenStreetCam that was also known as OpenStreetView, is a service dedicated to offering the real images of the most of the locations of the world.
Zenly - Zenly is a GPS tracker to locate your friends in realtime.