Square Seeks to Revolutionize Retail Sales With 'Square Register' for iPad and 'Card Case': Square, the company that has brought the ability to accept credit cards for transactions to individuals and small businesses with a card reader dongle for iOS devices, today announced its next venture: "Square Register" for iPad. Seeking to replace traditional cash registers with iPads equipped with the new Square Register application, Square notes that the app will allow businesses to easily customize the register interface with their full list of products.