Snapchat is an image messaging and multimedia mobile application. One of the principal concepts of Snapchat is that pictures and messages are only available for 24 hours before they become inaccessible. A "lens" feature, introduced in September 2015, allows users to add real-time effects into their snaps by using face detection technology which is activated by long-pressing on a face within the viewfinder.
A waving Cookie Monster featured as a filter on March 13, 2018. When the camera finds a face, Snapchat places cookie ears on the subject's head.