According to the strengthened regulation of Korean Government, beginning from 1st April 2020, whoever enters Korea should observe "self quarantine at home" or "quarantine in government desingated place" for 14days. In this regard, all Koreans and any long staying foreign nationals must install "Self Quarantine Safety Protection App." in their smart phone and register.
▶In regard to the previously informed application("COVID-19 Self-diagnosis Mobile App") is only for special visa holders such as diplomatic, official, official agreement ceremony, international conference for academic purpose or 'short term staying foreign nationals who hold
quarantine exemption certificate'.