Apple is flipping the switch on its iBeacon Bluetooth Low Energy sensors across its 254 US stores today. It’s the largest deployment of the technology into stores, and it will only work if you have the Apple Store app and have given it permission to track you. When you walk into the store, the app will go into “In-Store mode,” and it will let you know about deals in the areas around you. Ultimately, it’s nothing we haven’t seen before; we’ll just have to wait and see how consumers react, and whether the technology actually drives sales. For now, it’s still a shiny toy.