Starwood isn't the only hotel chain that wants you to use your smartphone as a hotel room key; Hilton is launching an initiative that lets you use your Android or iOS device to control virtually every aspect of your stay. Later this summer, a Hilton app will let you choose your preferred room, make special requests, check in and check out. You'll only have to speak to staff when it's time to pick up or return your keys. And in 2015, you won't even need to do that much -- your phone will also unlock your room, letting you make a beeline for your bed after a long flight.The rollout will take some time, but it should trump Starwood in terms of sheer scale. Room selection should be available in over 4,000 Hilton-affiliated hotels by the end of the year, including DoubleTree and Embassy Suites. Marriott will have check-in and check-out features at a similar number of locations by the end of the year, but Hilton's room selection and key features might give it an edge. Whichever hotel chain you prefer, the advancements are good news if you're a globetrotter -- you can spend more time sleeping, and less time waiting in line.