No eruv: carrying on Shabbat

There is no public eruv in Seoul or elsewhere in Korea that you should rely on, so plan as if you cannot carry in the public domain on Shabbat — keys, phones, strollers and the like. Choose accommodation within walking distance of where you'll daven and eat so you don't need to carry, arrange a non-electronic way back into your room (see the hotel note), and prepare food and settings before Shabbat begins. Confirm any specifics with the Chabad house.