Most Apple stores were sold out of the new iPhone by Sunday afternoon even though consumers had to wait hours to buy and activate them. Friday, Apple introduced the new version of the iPhone. It saw huge customer lines, and its system crashed as thousands of people worldwide tried to activate their new phones. Mark Siegel, a spokesperson for Apple’s wireless carrier partner AT&T, said Apple was “completely overwhelmed” by demand. Apple declined to comment. The iPhone sold out in New York, Los Angeles, Phoenix, Denver, Chicago, Boston and many other cities.