It's almost inevitable: release a new iPhone, break a sales record. This year, Apple released a pair of iPhones, the 5S and 5C, and unsurprisingly sales have been strong. Apple sold a combined 9 million iPhone 5S and 5C smartphones over the handsets' first full weekend of sales — the most it's ever done. That's enough for Apple to have already sold out of its initial stock of the iPhone 5S, though the company does say that retail stores are regularly receiving more shipments of the phone. "The demand for the new iPhones has been incredible," Apple CEO Tim Cook says in a statement. "We appreciate everyone’s patience and are working hard to build enough new iPhones for everyone.”