Gas
Anonymous compliments app targeted at teens in the USA. Launched August 2022, top app store within months. Bought by Meta January 2023, killed October 2023 after integration failure.
Mechanic: poll format like "who's the smartest in class?", user picks friends-from-school, the winner gets an anonymous "you're gassed!" notification. Classic feel-good engagement. Founders Nikita Bier, his attempt after tbh.app (anonymous compliments, Facebook-acquired 2017 — same pattern). Meta acquisition price $0.50/user — typical Meta pattern of buying viral teen apps + integrating/shutting down. Lesson: anonymous teen apps have growth-spike trajectories but hard-to-monetize organically. Modern descendant: Sendit, NGL — all same pattern (short-lived viral, founder acquihires).