Starwood hotels, the hotel chain that introduced the robotic butler, is offering a new revolutionary service: keyless check-in.

Through SPG Keyless feature of the Starwood app, hotel guests will be able to check in, get their room number and unlock their door using their mobile phone. The technology is currently being tested in 10 participating Starwood hotels around the world and will be available by early next year to all 150 Aloft, Element and W hotels.

The SPG Keyless feature is exclusive to all members of the Starwood Preferred Guest Program, regardless of their membership level.

In order to check in using the Starwood app, guests must sign up for push notifications so they can get their room number and Bluetooth key. The cool part is the ability to open their hotel room’s door by simply holding their phone against the door lock. A solid green light signals that the door has been unlocked.

SPG Keyless enables users to by-pass the check-in desk altogether and simply head straight to their room.

The Mobile Revolution

According to CNN, Starwood isn’t alone in the bid to replace archaic key cards. Hilton is also working on a similar technology, while most other major hotel chains are investing in mobile options for checking in and out to win over millennial customers.

Starwood Hotels and Resorts CEO Frits van Paasschen says mobile keys are not only convenient but also safer to use than actual key cards.

“If you lose your mobile device, you notice right away,” van Paasschen explained. “If you have to use your passcode to get into your phone, even if someone finds your phone they can’t get into your room.”

Starwood, the parent company that owns Sheraton, Westin and St. Regis hotels, says mobile keys are just the start of their mobile initiative.

“We’re increasingly going to upgrade the functionality of the app so you can do things like tell us where you are and what you want,” said Frits van Paasschen, Starwood Hotels and Resorts CEO. “We can start to send you offers targeted to exactly what you want.”

The Starwood app is available to iOS and Android users, but the SPG Keyless feature is only compatible with iPhone 4S and other iPhones running iOS8 as well as Android devices running Flavor 4.3 and above.

Mobile keys would especially prove useful with the rush of guests this holiday season.

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