I first saw Square at a concert. The indie band I'd gone to hear was selling t-shirts and CD's, then swiping credit cards on an iPhone via a small device inserted into the earphone jack. It was extremely efficient. Last week, I saw Square again at church. Since so few people carry cash anymore, they were using it to accept donations for Suubi necklaces in order to raise funds for the Uganda Children's Project.
Taking debit and credit cards used to require a great deal of backend set up, but with the digital world providing the functionality for small businesses to operate like large ones, Square meets a need.
Square makes it easy to get started. They provide the reader for free, and it only takes a few moments to set up your account. Then Square makes its money by charging a flat rate for all cards--2.75% per swipe. They also provide next day pay out to your bank account. There is no extra equipment, complicated contracts, monthly fees or merchant account required. In fact there is a beauty to the simplicity of it all.
Square is designed to work with iPhone, iPad and Android.
If you are a small church--or simply a small ministry within a big church--Square gives the ability to allow people to make transactions without cash, which can facilitate donations, event ticket sales, conference registrations, book/media sales and a host of other purchases.