Smart Sheriff (Korean: 스마트보안관) is a South Korean parental monitoring mobile app, introduced in 2015. It was developed by Korean app maker MOIBA, and is distributed free, sponsored by the South Korean government, which supported its development. The Korean government required its installation on the smart phones of all users who are under 19 years old, and the app allows the children's parents or guardians to monitor their online activity and block access to various websites. The regulation, passed by the Korea Communications Commission, required compliance from both telecom companies and the public. There was no opt-out provision, the telecom operators have to ensure its installation on all new phones sold to those under 19 years of age and failure to install the app rendered the phone una