Square Cash, also known as Cash App, is a mobile payment service that allows users to send and receive money quickly and easily. Launched by Square, Inc., it enables users to link their bank accounts or debit cards to transfer funds. The app is popular for its user-friendly interface and instant transactions. In addition to sending money, Cash App offers features like a debit card, investment options in stocks and Bitcoin, and the ability to receive direct deposits. It is available for both iOS and Android devices, making it accessible to a wide range of users.