① Naver Map / KakaoMap – public transportation and directions
② Papago – real-time Korean-English translation
③ Kakao T – taxi booking
④ Baedal Minjok / Coupang Eats – food delivery
⑤ KakaoPay / Naver Pay – mobile payment.
These apps are very useful when traveling in Korea, and you can use them smoothly with LG U+ data.