Scott Mayerowitz writes about the Starwood mobile room key which has launched today. Your SPG mobile app is your room key if you wish, although only so far at the following 10 hotels:

“W Downtown” is the New York property down by the World Trade Center.

The SPG app has been updated to include new functionality.

Your phone will use bluetooth — but requires actually being touched to the outside of the hotel room door in order to function because they don’t want you coming to the door from the inside, phone in hand, and accidentally opening the room to a stranger knocking.

So far only one phone can be paired to a room at a time, so if there are two guests in the room one can use the Starwood mobile room key but one will need a traditional key.

In general I love the Starwood mobile room key idea, and especially so as long as it remains an option. For a late night arrival I would love to go straight to my room. And at a conference with a busy check-in desk I would love to skip the line. Though the kiosks never took off, I had a soft spot for Sheraton’s as I won a contest in 2004 to name it (and got 60,000 Starpoints in return). Rather I had a soft spot for the concept more than the execution.

I don’t always love mobile check-in and not interacting with front desk staff because it means I can’t negotiate for an upgrade, and it means that I won’t find out nuances of a hotel and its particular elite benefits like whether breakfast can be taken in restaurant or via room service and how they prefer I access my free internet privileges (charging to the room and having it taken off, vs. access via a code given at check-in).

Starwood is first with this, but Hilton plans to have it rolled out to “all 4000 properties worldwide…by the end of the year.” Considering that it requires new locking hardware on each door, I’m skeptical of the timeframe. Hilton’s app will provide a hotel map to select a specific room.

At a minimum, this functionality makes the hotel app finally a must-have for your phone. Though Marriott is booking over $1 billion a year through their mobile platform, I still haven’t found much that I do better via mobile app than some other mechanism like my laptop. And so while I have both the SPG and Hyatt apps on my phone, I rarely use either. As Mayerowitz observes in the piece, hotels remain behind airlines with their apps.

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