A Beacon is a Bluetooth Low Energy device signaling it presence using iBeacon protocol. Each beacon contains some configuration data (unique id “which uniquely identifies a beacon or set of beacons as being of a certain type or from a certain organization” and major and minor identifier). These data can be used freely.

iOS7 can be declared as a Beacon and can monitor (detect there presence and measure there ditance) of other beacon, either iOS device or other devices.

This can be a “farther” competitor of NFC opening new type of interactions:

  • a museum app can detect which in wich hall your are and even wich masterpiece is nearest you,
  • a mall can provides you targeted information or discount vouchers for only surrounding stores
  • social app can warn you your friends are near you.

iBeacons | Dave Addey.

EDIT: An implementation for Android 4.3 is available here: https://github.com/RadiusNetworks/android-ibeacon-service.