Square Register Card Case Square Register Card Case. Square recently introduced Card Case, a new app that essentially turns smartphones into digital cash registers at local businesses. Even though it’s very new, one has to ask, can this work? The idea behind the app seems simple enough: ring up items all on the iPhone’s screen, pay with a saved credit card file and a text message receipt is delivered. Until NFC technology is integrated into most smartphones, apps like this could fill a significant void. Smartphone owners are typically more tech savvy and fond of making the most out of their handhelds. The closest (and probably most successful) app would be the Starbucks app for the iPhone, which is tethered to a gift card account with a credit card on file for automatic refills (of cash, not coffee). Square’s new app includes a directory local restaurants and cafes (I can almost see a daily deal feature here in the future) along with menus and records of digital receipts. So far, that ...