Sam Grobart reviews the Bluetooth Low Energy (BLE) technology used by the Apple iBeacon and its potential retail importance.

Designed for short distances (about 150 feet or less), BLE enables your phone to announce its presence to other devices in range in an extremely power-efficient way. With iBeacon, any iOS 7 device becomes a potential BLE beacon, already in place in every new and updated iPhone and iPad. Retailers can make their spaces iBeacon-friendly by purchasing dedicated beacons, like the $99 three-pack from Estimote.