PayPal is currently the leading digital payments provider but that could all change in the near future. Mobile payments company Square has launched a new service that allows anyone with a debit card to send cash to anyone else at any time just by sending an e-mail.

The service has been in beta since May but is finally ready for prime time. Using Square Cash sounds easy enough - just address an e-mail to the person you want to pay, add a CC: to and put the amount you want to send in the subject line. The body of the message can contain any text you want such as a memo regarding the transaction for your records or just a friendly "hello."

First-time users will receive an e-mail from Square asking them to visit the Square Cash website to enter in their debit card number. This only happens once, we're told, and when funds are delivered, they are sent directly to your bank account instead of an online account like PayPal.

The service is free of charge (no hidden fees) and the money is deposited into the destination account within 1-2 business days (PayPal can take upwards of 3-4 days to transfer money). Neither person in the transaction is required to have a Square account and you can send up to $2,500 per week. Square did say that if they add new features in the future, they might introduce a fee.