The app then uses that UUID to figure out a course of action. For example, a museum may designate a specific beacon's UUID to indicate a beacon in the tyrannosaurus exhibit, so the museum app can pull up pictures, videos, audio descriptions, and so forth about that dinosaur. A savvy museum app would check the phone's default language and automatically use it in what it displays or plays. It would also provide directions to related exhibits and engage with other beacons it encounters along the way to follow the user and adjust its recommendations or directions.
iOS's iBeacons protocol provides very little information from the beacon -- just its UUID. Likewise, it provides only the UUID of the device to the app, with no other user information. That leaves the smarts to the app, and it keeps the user private. You could use beacons to count the number of devices that come by your store or exhibit, as a proxy for the number of people, but you wouldn't know who came by. (Of course, if a user provides personal information to the app, the app's creator can associate the mobile device's UUID to an actual individual.)
Other operating systems don't have the iBeacons protocol or APIs, and so far Google and Microsoft haven't developed an iBeacons-like API and protocol for their mobile platforms (Android and Windows Phone, respectively). But they can still use beacons -- if their app developers adopt any of the APIs that the various beacons providers have developed. In these early days, lack of native Android support has not dissuaded businesses from starting beacons efforts, notes Onyx's Foeckl; the iOS installed base is sufficiently large to justify at least pilot rollouts.
Of course, the problem is that apps using a specific vendor's beacons APIs typically will work only with that vendor's beacons, as there is as yet no industrywide standard. The iOS world doesn't have the lock-in issue because every beacons vendor has, or will very soon, add iBeacons API and protocol support to their beacons. But iBeacons is iOS-only, so it doesn't help the larger Android or smaller Windows Phone communities.
The shape of beacons to come
Several beacon makers offer richer options though proprietary APIs and protocols that can do more than iBeacons does, yet their hardware still uses iBeacons for initial OS-level auto-detection and app alerting in iOS. Those vendors include Estimote, Gimbal, Onyx Beacons, and StickNFind.
As an example, StickNFind creates custom firmware for its customers, aimed at vertical industry needs. Its S Beacons protocol also communicates more than the beacon's UUID, says COO Lior Gan-El; the beacon can transmit temperature and battery life, as well as logs on successful pairings with other devices (active connections, versus passive ones), and even user-defined packets. If this sounds a lot like active RFID transponders of a decade ago, it is. The notion is the same, he says, but the ubiquity of Bluetooth on broadly available devices means that notion can now be implemented easily and at scale.