Hilton Worldwide, one of the biggest hotel conglomerates on earth, has announced a seismic foray into the mobile realm, with new technology that will enable guests at over 4,000 properties worldwide to reserve and customize their rooms -- and even open hotel doors -- all with the touch of a smartphone.

Though Hilton introduced digital check-ins more than five years ago, now guests will be able to “choose their exact room from digital floor plans,” purchase upgrades, make other special amenity requests and check out -- all from their mobile devices.

The capabilities, which Hilton referred to in a press release as a “first for the hospitality industry,” will be enacted by year’s end in more than 650,000 rooms in 80 countries. The nearly century-old company operates 11 hotel brands, including Waldorf Astoria, DoubleTree, Embassy Suites and more. The Wall Street Journal places the total cost of the implementation at $550 million.

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Beyond reservations, the company will also enable guests to bypass the check-in desk entirely with technology that turns their smartphones into room keys, arriving next year.

“Travelers can use their smartphones as boarding passes to get to their seats on an airplane,” said Hilton president and CEO, Christopher Nassetta, in a statement. “So it is only natural that they will want to use them as a way to enter their hotel rooms.”

Such increased mobile activity may spell job losses for Hilton hotel staffers -- or, as the Journal puts it, enable the company to “run a leaner operation that is likely to reap savings.”

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Nevertheless, the initiative takes square aim at a host of competitors that are also dipping their toes into the mobile pool, the Journal reports -- although to a somewhat lesser degree.

Starwood Hotels & Resorts Worldwide is piloting mobile keys at a handful of its locations, while Marriott International and InterContinental Hotels send guests text alerts with promotional offers including discounted spa treatments and drink specials.

Hilton is also looking to take away business from booking sites like Expedia.com, which charges hotels a fee for every reservation tendered.

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