Square is a new product which allows merchants to accept credit card payments using an iPhone. It relies on a physical device, which plugs into the iPhone’s audio jack, to scan the credit cards. Receipts can then be retrieved digitally online. I believe the name for this was previously rumored as the “Acorn,” though I suppose it was adapted to reflect a change in the devices shape. The product comes primarily from Twitter inventor, Jack Dorsey, and has a rock-star team of developers and designers behind it.
