In Pictures: How Apple's iBeacon works
Apple's iBeacon is already in many iPhones, whether you realise it or not. The technology was rolled out in several Apple store locations back in December, and had many privacy advocates concerned about the implications for user tracking and security. Here's a breakdown of how it works.
iBeacon is an Apple specification that extends location services in iOS to include Bluetooth Low Energy (BLE) devices, specifically a broadcasting BLE radio called a beacon. It has the potential to usher in a new level of interactivity for the mobile user experience. Here’s how it works.
In your iPhone, iOS alerts apps when you come in range of a broadcasting iBeacon. The app can monitor location, estimate your distance to the beacon, and define the location based on the BLE signal instead of on GPS. iBeacon is already starting to change the mobile user experience. Here’s how it works.
iBeacon is based on the BLE features introduced in Bluetooth 4.0, extending the radio’s range and improving power efficiency so it can run for months, even years, on batteries. Apple was the first major vendor to bring this to a mass market in the iPhone 4S, adding it to other iOS and OS X devices later. A “Bluetooth Smart” device uses only the low-energy features; a “Bluetooth Smart Ready” device can connect both to “Bluetooth Classic” and “Bluetooth Smart” devices.
On top of the BLE protocol stack, Apple created first what it calls Core Bluetooth, a set of classes that lets iOS apps easily call the underlying BLE functions.
The actual iBeacon also incorporates a BLE radio, usually powered by a some kind of battery, and mounted (sometimes with an adhesive backing) on a doorway, wall, or aisle. The iBeacon broadcasts a Bluetooth signal in the 2.4-Ghz band within a preset range. Conventional Bluetooth reaches about 30 feet, but with BLE can go over 200 (the spec doesn’t impose a limit). Shown: an exploded view of an iBeacon from Estimote.
Another group of beacons, from SonicNotify, showing the variety of form factors, sizes, and housings for beacons.
All iPhones from iPhone 4S onwards support Bluetooth 4.0. Any iOS device with that radio and iOS 7 – and with both Location Services and Notifications turned on -- can sense an iBeacon broadcast and respond. Typically, iBeacons greet users with an invitation to download an app or, if you have their app already, some other content such as a sales items, a daily special, coupon, etc. The user has to explicitly accept the invitation.
These screenshots show how Apple’s iBeacons, in its own retail stores, invite users to enable iBeacon notifications. Once enabled, the central screen appears, a kind of dashboard to the store’s offers, help, and reminders. Based on your Apple ID and associated credit cards, you can complete a purchase with your iPhone.
This diagram shows, for a retail setting, the range of content and capabilities that iBeacon’s location services can enable.
As this diagram shows, the iBeacon has minimal communication with the iPhone: it’s a kind of digital tripwire when your iPhone’s BLE radio comes within range. IBeacon can locate you, and alert you to the fact that there are notifications that may be of interest to you. But the actual content, including apps, is downloaded to the phone from servers in a private or public cloud, via Wi-Fi or cellular.
For SuperBowl week, the NFL sprinkled iBeacons along “SuperBowl Boulevard” a stretch of Broadway near Times Square, and updated its “N.F.L. Mobile” iOS app. The beacons popped up different notifications as you walked among the events, exhibits, and activities. Most iBeacon deployments right now are experiments to discover how the marriage of your identity and your location can be used in evolving the mobile user experience.