• Fast Company, Tuesday, May 11, 2010 1:24 PM

Meet Square -- a just-launched app that aims to simplify credit card sales for any retailers with an iPhone or Android OS-supported smartphone. With Square, anyone can accept credit or debit card payments by downloading the app and plugging what Fast Company describes as "a little plastic cube" into the headphone jack of their iPhone, iPod Touch, iPad, or Android phone. After a swiping the card through the reader, merchants turn the device over to customers to sign their names on the touchscreen using a finger instead of a pen.

Customer can then add a tip, either by percentage or a particular amount, and then enter their phone number or email address. Jack Dorsey is the brains behind Square, as well as cofounder and chairman of Twitter. The fee charged for each transaction on Square is 2.75% plus 15 cents -- "Not the lowest available, but it's a reliable fee regardless of the type of card used," according to Fast Company.

Read the whole story at Fast Company »