A newly launched fitness app becomes extremely popular

Solution

The Bandwagon Effect occurs when individuals adopt a certain behavior, style, or attitude because they see others doing it ("jumping on the bandwagon"). In this scenario, people are subscribing to the app not for personal fitness, but to be part of the growing group of followers and for social conformity, which is the definition of the bandwagon effect.   Kindly note, herding behavior is similar to the bandwagon effect but not exactly same. Herding is typically used in the context of financial markets or to describe a fear-driven, panic, or blind following, without own research with a belief that others know something, you do not know yet. Whereas the Bandwagon Effect specifically describes adoption driven by popularity, social status, and the desire to fit in.    Anchoring bias is relying too heavily on the first piece of information offered when making decisions. Commitment bias is the tendency to remain committed to past behaviours, even if they no longer yield desirable outcomes.   Availability heuristic is making decisions based on immediate examples that come to a person's mind.