Is Location Sensor working in South Korea?

Sorry; I can test that; what I can tell you is that it is working everywhere else in the world.

Yes. You can try the aia and tutorial

Be aware, to work; your device must have a GPS receiver, you must test your device near a window or outside (so the gps receiver can get a signal from the gps satellites) and your device Location Setting must be set to allow Location and gps.

Why not try the tutorial, load the aia then report on your results?