LINE is a messaging app launched in Japan in 2011 that grew into one of the most widely used communication platforms across East and Southeast Asia, where its calls and messages are part of everyday life. Its distinctive ringtone became instantly familiar to millions of users, so short clips of it began circulating on soundboards and in online videos as a quick way to signal a phone call. It remains popular because the sound is immediately recognisable, even to people who do not use the app themselves.