Here is the English translation of the advice for your friend. General Advice for Traveling in Korea Public Transport: Seoul and Busan have well-developed public transportation. Riding the subway will be a fun experience in itself. Safety: It is extremely safe. There are no pickpockets on the subway. Dining: Eating out is not expensive. There is no tipping culture, and you don’t need to order dessert; just ordering the main dish is fine. A typical meal often costs less than 10 CHF. Photos: If you ask Koreans to take a picture of you, they will gladly take excellent photos. (Young women are particularly kind and helpful). Taxis: Taxis are surprisingly cheap compared to other countries. However, some drivers may take a longer route to the destination, so I recommend limiting taxi use to just once or twice. Also, using taxis can be inconvenient without a dedicated taxi app. Navigation: Seoul and Busan are huge cities, so you should plan your itinerary by "blocks" (distri...