Region: US | Usage example: After seeing everyone else using the new app, she jumped on the bandwagon and downloaded it too.

Jump on the bandwagon

Meaning

Adopt a popular trend or join others in doing something.

Often carries a playful or critical tone about copying popularity.

Origin notes can vary by region and source; this page gives the commonly reported explanation and usage context.

From political parades where politicians rode marching bands; the term encouraged supporters to climb aboard the wagon.

19th-century American politics coined it, and it later spread into general use for movements or trends.