Venmo is a mobile payment service owned by PayPal. Venmo account holders can transfer funds to others via a mobile phone app; both the sender and receiver have to live in the U.S. It handled $159 billion in transactions in the first quarter of 2018. Venmo was launched in 2009 targeting friends splitting bills, e.g. for movies, dinner, rent, tickets, etc.
By default, Venmo publishes every peer-to-peer transaction (excluding the amount), a feature shown by researchers to reveal sensitive details about users' lives in some situations. In 2018, the company settled with the FTC about several privacy and security violations related to this and other features, and made changes to the corresponding settings, but it continued to attract criticism for exposing users to privacy risks.