Smartphones will work as Hilton hotel room keys in 2015

Hilton, spurred by growing competition, has announced that its hotels will allow customers to take self-check-ins one step further, using their iPhone or Android handset as a room key. The feature won't start arriving until 2015, but when it does, it'll arrive at six of the company's hotel brands. The Wall Street Journal is reporting that this is a $550 …