Bluetooth Low Energy in public spaces

This lower-cost technology could greatly enhance consumer convenience for many applications.

I’ve been thinking a lot about the new low-energy form of Bluetooth (BLE) recently, with an eye toward thinking about ways it can be used. The core advantages the protocol has over other similar standards is that it’s optimized for lower data rates, and extremely long battery life. While we may complain about how much energy a Wi-Fi device uses, it’s acceptable to charge your phone once a day. If we could eliminate the need to recharge, what lower-data rate applications could we build?

The most obvious application of something like BLE is that it communicates over a shorter range, and therefore, can provide precise location information. Companies like Euclid Analytics measure foot traffic by using Wi-Fi signals, so the precision of the location is fairly rough. BLE devices have a smaller operating range, and thus would be able to provide information on what aisle a person is in instead of a broad area of the store. (And yes, there are obvious privacy concerns here, especially given that many users tend to accept all the privileges requested by an app running on their phone, which might make BLE-enabled location personally identifiable.)

An alternative way of using BLE to support purchasing is that it allows locations to describe themselves. Say, for example, that my favorite pizza place has put in a BLE “beacon” that announces itself to the world, and they have created an app for my smartphone that lets me order. I place the order for a pizza with my app. When I walk into the store, my phone is listening for the BLE beacon, wakes up, and uses a network connection (either Wi-Fi or 4G) to tell the store computer that I have arrived to pick up order number whatever, and it charges a credit card on file to give me an electronic receipt. Charging could be done through a merchant account, or even PayPal or Square, which would make it easier for a small take-out restaurant to perform this task. At a busy pizza place, not having to handle payments can speed up the line substantially. (Privacy is a substantially smaller concern in this case because there isn’t much to analyze that the company would not have already known from their cash register.) In this case, BLE is used to wake up a higher-speed interface so that the higher-speed, and likely higher-power, interface can stay asleep for much of the time.

Many busy restaurants hand out wireless discs to tell you when your table is ready. In a slightly different version of the BLE-triggered payment, when you walk into a restaurant, your phone could notice it is in a restaurant due to the presence of a BLE beacon. At this point, an app on the phone could automatically check you in with the host. Conceivably, an app could monitor on-time performance of seating for the restaurant’s management.

A more generic form of queue management would be to monitor when you enter a line and when you exit by using BLE devices at the entry and exit points of the queue. Banks, for instance, might be interested in using queue analytics to determine the right number of tellers to staff. As a frequent traveler, real-time measurements of wait times at security checkpoints would be fabulous as well.

BLE is exciting because it’s a relatively inexpensive technology that can allow applications to gather highly detailed information about the physical world. Apps can learn about where they are and what they are near without needing to rely on a massive GPS database, and mobile devices can gather data that today is too labor-intensive to create and too difficult to report in real time.

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  • If you can limit the range to something like three feet instead of 160, it would open up some useful functions based on “I’m really very close”. Using it to synch with a key server in the security office is a technical one, and having a screen-saver see that I’m back from the washroom is a more prosaic use.

    • Matthew Gast

      Beacons have tunable power. I was using a RadBeacon from Radius Networks last night, and once I calibrated the signal, it gave me a pretty accurate readout on the distance from the beacon (in meters, not feet). Apple’s location API divides you into “near” and “far” depending on how strongly the signal is received.

      • Thanks!
        Of course, that raises a cool attack on the projector-and-keybord set in the boardroom: while I’m trying to authenticate via bluetooth to show a slide, someone else in the room turns their signal strength up to max and metaphorically yanks the keyboard out from under my fingers (;-))

        • Matthew Gast

          Beacons are transmit-only. You need an app on the device to take action, and the communication may take place over some other network connection. In the payment example, you walk into the store, detect a beacon, and then fire up an app to connect over Wi-Fi and process the payment. The beacon has no idea you were there.

          For the fully nuanced take, see this article by Chris Sexton:

          (This is not to say that stealing a Bluetooth connection isn’t a security threat — it is! It is just not a threat triggered by beacons.)

          • Thanks: I’d not realized that beacons were special: I’ll read the reference next time (;-))

          • Matthew Gast

            Don’t worry about it! There is a lot of confusion between “BLE” and “beacons.” Maybe this is a future post?

  • tmeyer2000

    These are all very cool use-cases. However managing beacons with a 1 to 1.5 year lifetime will be a nightmare. Who will be responsible for going around changing batteries? Vandalism could be another problem.

    • Matthew Gast

      That’s clearly a problem that we need to solve. Most beacons will report battery life, but you still need to build a management application that can report battery life trickling away.

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  • rabit

    With the increased dependence on low-energy Bluetooth on our phones for our everyday needs comes the need for more public phone charging stations. Yes.

  • BLE is hot right now for both consumer and industry markets. A few Twitter searches for BLE and related keywords pull up quite a number of innovations in both spaces.

    Good write up, Matthew.