For anyone who wishes to plan their vacation in Korea, I will strongly recommend all of you to download an free app called Jihachul. I never heard of this app until my hostel's owner recommended me to download this mobile app.
It contains the subway route maps in Korea and also calculates how long it takes to travel from one station to another. It would be much easier for me plan for my itinerary if I have heard of this application before I went to Korea. It has both android and Mac version and very easy to use. All the station's name are in English.
Jihachul - A must-have app before you go to Korea
