Snapchat

Snapchat built its identity on messages that disappear after viewing, and that framing still shapes how it is used: casual, private exchanges between close friends rather than public broadcasting.

Its camera features — face filters and augmented-reality lenses — remain a genuine technical strength, and brands can publish their own lenses as a form of advertising that people choose to use rather than skip.

Its audience skews young and Western, with strong penetration among teenagers and people in their twenties in North America and parts of Europe. Outside that demographic its reach drops sharply, so it suits some campaigns and is irrelevant to others.