Tied to a super-clever smartphone and leveraging secure network connections and mobile Net, it turns out that NFC phones make a very good key.
Throughout their long history keys have had two very specific properties that are intertwined. First they physically exist to undo locks--thereby giving access to what's contained behind the lock. And they also confer/imply authority on the keyholder as being privileged to have access ... which is why we keep keys secret, safe. This second aspect of identifying the keyholder is actually as important as the first, although it's always been a problem for physical keys--because the key itself can be stolen, and thus used by someone who doesn't have access privileges.
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That all changes with modern digital keys that are smart and can positively identify the holder as having access rights. And the pinnacle of this tech evolution is the smartphone--something that Samsung is putting to good use  in an impressive new installation in London for the Olympics. It's just announced an amazing solution that it's installing in the new Holiday Inn London Stratford City hotel, right next to Olympic Park. Via a special app on Galaxy S III smartphones, hotel guests will be able to make express check-ins and check-out of the hotel and also to use their phone's NFC powers to unlock the digital security locks of their rooms.
That's clever enough because it uses possession of the phone and security protocols to positively identify the phone's owner as having the right to unlock a door, and then to also securely access the locking mechanism--technically, this is the ultimate key. You don't even have to carry a physical key around with you in addition to your phone, as you would with a low-tech key, and once your stay is over it's a simple matter to de-authorize a your phone from accessing the hotel's facilities.
But Samsung's system actually teaches us a whole lot more about the future of smartphone "keys." Once inside the room, the same phone can be used to order room and laundry service, book other hotel facilities, and act as an in-room phone extension. Because of the Olympics tie-in, the special app also gives localized content to the hotel guest, and Olympic Games information including results. It can also control the hotel room TVs, lighting and AC and other in-room electronics. And it can provide "location based offers."
That's something Samsung's press release glosses over, but it's actually the most exciting part of the entire integrated package. By using the smartphone's data links, clever systems to positively identify the user of the phone including tying the guest's location absolutely to a hotel room via the NFC unlock, Samsung and Holiday Inn can identify the user and probably glean some sense of their personal desires. This lets them partner with advertisers who can then target their special offers or ads to a particular location and/or demographic...right through the same system the hotel guest is using as their smart room key. The app is essentially a very potent way to introduce hotel guests to entirely new places, experiences and products which ad partners think they may be interested in--as a by-product of its main "digital hotel key and services" function.
Think beyond a system like this in a hotel, and see the day not far down the road when you may use your smartphone key to unlock your car, or to positively ID yourself and gain access to a night-time ATM lobby in a bank, or to unlock your front door. Each of these moments of unlocking ties you to an identity and a location, and that's incredibly valuable information for future hyper-local advertising.
That old Yale doorkey in your pocket... It's looking prehistoric right now, isn't it?